${bits_srcdir}/charconv.h \
${bits_srcdir}/codecvt.h \
${bits_srcdir}/concept_check.h \
+ ${bits_srcdir}/cow_string.h \
${bits_srcdir}/cpp_type_traits.h \
${bits_srcdir}/deque.tcc \
${bits_srcdir}/enable_special_members.h \
${bits_srcdir}/charconv.h \
${bits_srcdir}/codecvt.h \
${bits_srcdir}/concept_check.h \
+ ${bits_srcdir}/cow_string.h \
${bits_srcdir}/cpp_type_traits.h \
${bits_srcdir}/deque.tcc \
${bits_srcdir}/enable_special_members.h \
# include <string_view>
#endif
+#if ! _GLIBCXX_USE_CXX11_ABI
+# include "cow_string.h"
+#else
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
+_GLIBCXX_BEGIN_NAMESPACE_CXX11
#ifdef __cpp_lib_is_constant_evaluated
// Support P1032R1 in C++20 (but not P0980R1 yet).
#elif __cplusplus > 201703L
#endif
-#if _GLIBCXX_USE_CXX11_ABI
-_GLIBCXX_BEGIN_NAMESPACE_CXX11
/**
* @class basic_string basic_string.h <string>
* @brief Managing sequences of characters and character-like objects.
template<typename, typename, typename> friend class basic_stringbuf;
};
_GLIBCXX_END_NAMESPACE_CXX11
-#else // !_GLIBCXX_USE_CXX11_ABI
- // Reference-counted COW string implentation
-
- /**
- * @class basic_string basic_string.h <string>
- * @brief Managing sequences of characters and character-like objects.
- *
- * @ingroup strings
- * @ingroup sequences
- *
- * @tparam _CharT Type of character
- * @tparam _Traits Traits for character type, defaults to
- * char_traits<_CharT>.
- * @tparam _Alloc Allocator type, defaults to allocator<_CharT>.
- *
- * Meets the requirements of a <a href="tables.html#65">container</a>, a
- * <a href="tables.html#66">reversible container</a>, and a
- * <a href="tables.html#67">sequence</a>. Of the
- * <a href="tables.html#68">optional sequence requirements</a>, only
- * @c push_back, @c at, and @c %array access are supported.
- *
- * @doctodo
- *
- *
- * Documentation? What's that?
- * Nathan Myers <ncm@cantrip.org>.
- *
- * A string looks like this:
- *
- * @code
- * [_Rep]
- * _M_length
- * [basic_string<char_type>] _M_capacity
- * _M_dataplus _M_refcount
- * _M_p ----------------> unnamed array of char_type
- * @endcode
- *
- * Where the _M_p points to the first character in the string, and
- * you cast it to a pointer-to-_Rep and subtract 1 to get a
- * pointer to the header.
- *
- * This approach has the enormous advantage that a string object
- * requires only one allocation. All the ugliness is confined
- * within a single %pair of inline functions, which each compile to
- * a single @a add instruction: _Rep::_M_data(), and
- * string::_M_rep(); and the allocation function which gets a
- * block of raw bytes and with room enough and constructs a _Rep
- * object at the front.
- *
- * The reason you want _M_data pointing to the character %array and
- * not the _Rep is so that the debugger can see the string
- * contents. (Probably we should add a non-inline member to get
- * the _Rep for the debugger to use, so users can check the actual
- * string length.)
- *
- * Note that the _Rep object is a POD so that you can have a
- * static <em>empty string</em> _Rep object already @a constructed before
- * static constructors have run. The reference-count encoding is
- * chosen so that a 0 indicates one reference, so you never try to
- * destroy the empty-string _Rep object.
- *
- * All but the last paragraph is considered pretty conventional
- * for a C++ string implementation.
- */
- // 21.3 Template class basic_string
- template<typename _CharT, typename _Traits, typename _Alloc>
- class basic_string
- {
- typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template
- rebind<_CharT>::other _CharT_alloc_type;
- typedef __gnu_cxx::__alloc_traits<_CharT_alloc_type> _CharT_alloc_traits;
-
- // Types:
- public:
- typedef _Traits traits_type;
- typedef typename _Traits::char_type value_type;
- typedef _Alloc allocator_type;
- typedef typename _CharT_alloc_traits::size_type size_type;
- typedef typename _CharT_alloc_traits::difference_type difference_type;
-#if __cplusplus < 201103L
- typedef typename _CharT_alloc_type::reference reference;
- typedef typename _CharT_alloc_type::const_reference const_reference;
-#else
- typedef value_type& reference;
- typedef const value_type& const_reference;
-#endif
- typedef typename _CharT_alloc_traits::pointer pointer;
- typedef typename _CharT_alloc_traits::const_pointer const_pointer;
- typedef __gnu_cxx::__normal_iterator<pointer, basic_string> iterator;
- typedef __gnu_cxx::__normal_iterator<const_pointer, basic_string>
- const_iterator;
- typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
- typedef std::reverse_iterator<iterator> reverse_iterator;
-
- protected:
- // type used for positions in insert, erase etc.
- typedef iterator __const_iterator;
-
- private:
- // _Rep: string representation
- // Invariants:
- // 1. String really contains _M_length + 1 characters: due to 21.3.4
- // must be kept null-terminated.
- // 2. _M_capacity >= _M_length
- // Allocated memory is always (_M_capacity + 1) * sizeof(_CharT).
- // 3. _M_refcount has three states:
- // -1: leaked, one reference, no ref-copies allowed, non-const.
- // 0: one reference, non-const.
- // n>0: n + 1 references, operations require a lock, const.
- // 4. All fields==0 is an empty string, given the extra storage
- // beyond-the-end for a null terminator; thus, the shared
- // empty string representation needs no constructor.
-
- struct _Rep_base
- {
- size_type _M_length;
- size_type _M_capacity;
- _Atomic_word _M_refcount;
- };
-
- struct _Rep : _Rep_base
- {
- // Types:
- typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template
- rebind<char>::other _Raw_bytes_alloc;
-
- // (Public) Data members:
-
- // The maximum number of individual char_type elements of an
- // individual string is determined by _S_max_size. This is the
- // value that will be returned by max_size(). (Whereas npos
- // is the maximum number of bytes the allocator can allocate.)
- // If one was to divvy up the theoretical largest size string,
- // with a terminating character and m _CharT elements, it'd
- // look like this:
- // npos = sizeof(_Rep) + (m * sizeof(_CharT)) + sizeof(_CharT)
- // Solving for m:
- // m = ((npos - sizeof(_Rep))/sizeof(CharT)) - 1
- // In addition, this implementation quarters this amount.
- static const size_type _S_max_size;
- static const _CharT _S_terminal;
-
- // The following storage is init'd to 0 by the linker, resulting
- // (carefully) in an empty string with one reference.
- static size_type _S_empty_rep_storage[];
-
- static _Rep&
- _S_empty_rep() _GLIBCXX_NOEXCEPT
- {
- // NB: Mild hack to avoid strict-aliasing warnings. Note that
- // _S_empty_rep_storage is never modified and the punning should
- // be reasonably safe in this case.
- void* __p = reinterpret_cast<void*>(&_S_empty_rep_storage);
- return *reinterpret_cast<_Rep*>(__p);
- }
-
- bool
- _M_is_leaked() const _GLIBCXX_NOEXCEPT
- {
-#if defined(__GTHREADS)
- // _M_refcount is mutated concurrently by _M_refcopy/_M_dispose,
- // so we need to use an atomic load. However, _M_is_leaked
- // predicate does not change concurrently (i.e. the string is either
- // leaked or not), so a relaxed load is enough.
- return __atomic_load_n(&this->_M_refcount, __ATOMIC_RELAXED) < 0;
-#else
- return this->_M_refcount < 0;
-#endif
- }
-
- bool
- _M_is_shared() const _GLIBCXX_NOEXCEPT
- {
-#if defined(__GTHREADS)
- // _M_refcount is mutated concurrently by _M_refcopy/_M_dispose,
- // so we need to use an atomic load. Another thread can drop last
- // but one reference concurrently with this check, so we need this
- // load to be acquire to synchronize with release fetch_and_add in
- // _M_dispose.
- return __atomic_load_n(&this->_M_refcount, __ATOMIC_ACQUIRE) > 0;
-#else
- return this->_M_refcount > 0;
-#endif
- }
-
- void
- _M_set_leaked() _GLIBCXX_NOEXCEPT
- { this->_M_refcount = -1; }
-
- void
- _M_set_sharable() _GLIBCXX_NOEXCEPT
- { this->_M_refcount = 0; }
-
- void
- _M_set_length_and_sharable(size_type __n) _GLIBCXX_NOEXCEPT
- {
-#if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
- if (__builtin_expect(this != &_S_empty_rep(), false))
-#endif
- {
- this->_M_set_sharable(); // One reference.
- this->_M_length = __n;
- traits_type::assign(this->_M_refdata()[__n], _S_terminal);
- // grrr. (per 21.3.4)
- // You cannot leave those LWG people alone for a second.
- }
- }
-
- _CharT*
- _M_refdata() throw()
- { return reinterpret_cast<_CharT*>(this + 1); }
-
- _CharT*
- _M_grab(const _Alloc& __alloc1, const _Alloc& __alloc2)
- {
- return (!_M_is_leaked() && __alloc1 == __alloc2)
- ? _M_refcopy() : _M_clone(__alloc1);
- }
-
- // Create & Destroy
- static _Rep*
- _S_create(size_type, size_type, const _Alloc&);
-
- void
- _M_dispose(const _Alloc& __a) _GLIBCXX_NOEXCEPT
- {
-#if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
- if (__builtin_expect(this != &_S_empty_rep(), false))
-#endif
- {
- // Be race-detector-friendly. For more info see bits/c++config.
- _GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE(&this->_M_refcount);
- // Decrement of _M_refcount is acq_rel, because:
- // - all but last decrements need to release to synchronize with
- // the last decrement that will delete the object.
- // - the last decrement needs to acquire to synchronize with
- // all the previous decrements.
- // - last but one decrement needs to release to synchronize with
- // the acquire load in _M_is_shared that will conclude that
- // the object is not shared anymore.
- if (__gnu_cxx::__exchange_and_add_dispatch(&this->_M_refcount,
- -1) <= 0)
- {
- _GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER(&this->_M_refcount);
- _M_destroy(__a);
- }
- }
- } // XXX MT
-
- void
- _M_destroy(const _Alloc&) throw();
-
- _CharT*
- _M_refcopy() throw()
- {
-#if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
- if (__builtin_expect(this != &_S_empty_rep(), false))
-#endif
- __gnu_cxx::__atomic_add_dispatch(&this->_M_refcount, 1);
- return _M_refdata();
- } // XXX MT
-
- _CharT*
- _M_clone(const _Alloc&, size_type __res = 0);
- };
-
- // Use empty-base optimization: http://www.cantrip.org/emptyopt.html
- struct _Alloc_hider : _Alloc
- {
- _Alloc_hider(_CharT* __dat, const _Alloc& __a) _GLIBCXX_NOEXCEPT
- : _Alloc(__a), _M_p(__dat) { }
-
- _CharT* _M_p; // The actual data.
- };
-
- public:
- // Data Members (public):
- // NB: This is an unsigned type, and thus represents the maximum
- // size that the allocator can hold.
- /// Value returned by various member functions when they fail.
- static const size_type npos = static_cast<size_type>(-1);
-
- private:
- // Data Members (private):
- mutable _Alloc_hider _M_dataplus;
-
- _CharT*
- _M_data() const _GLIBCXX_NOEXCEPT
- { return _M_dataplus._M_p; }
-
- _CharT*
- _M_data(_CharT* __p) _GLIBCXX_NOEXCEPT
- { return (_M_dataplus._M_p = __p); }
-
- _Rep*
- _M_rep() const _GLIBCXX_NOEXCEPT
- { return &((reinterpret_cast<_Rep*> (_M_data()))[-1]); }
-
- // For the internal use we have functions similar to `begin'/`end'
- // but they do not call _M_leak.
- iterator
- _M_ibegin() const _GLIBCXX_NOEXCEPT
- { return iterator(_M_data()); }
-
- iterator
- _M_iend() const _GLIBCXX_NOEXCEPT
- { return iterator(_M_data() + this->size()); }
-
- void
- _M_leak() // for use in begin() & non-const op[]
- {
- if (!_M_rep()->_M_is_leaked())
- _M_leak_hard();
- }
-
- size_type
- _M_check(size_type __pos, const char* __s) const
- {
- if (__pos > this->size())
- __throw_out_of_range_fmt(__N("%s: __pos (which is %zu) > "
- "this->size() (which is %zu)"),
- __s, __pos, this->size());
- return __pos;
- }
-
- void
- _M_check_length(size_type __n1, size_type __n2, const char* __s) const
- {
- if (this->max_size() - (this->size() - __n1) < __n2)
- __throw_length_error(__N(__s));
- }
-
- // NB: _M_limit doesn't check for a bad __pos value.
- size_type
- _M_limit(size_type __pos, size_type __off) const _GLIBCXX_NOEXCEPT
- {
- const bool __testoff = __off < this->size() - __pos;
- return __testoff ? __off : this->size() - __pos;
- }
-
- // True if _Rep and source do not overlap.
- bool
- _M_disjunct(const _CharT* __s) const _GLIBCXX_NOEXCEPT
- {
- return (less<const _CharT*>()(__s, _M_data())
- || less<const _CharT*>()(_M_data() + this->size(), __s));
- }
-
- // When __n = 1 way faster than the general multichar
- // traits_type::copy/move/assign.
- static void
- _M_copy(_CharT* __d, const _CharT* __s, size_type __n) _GLIBCXX_NOEXCEPT
- {
- if (__n == 1)
- traits_type::assign(*__d, *__s);
- else
- traits_type::copy(__d, __s, __n);
- }
-
- static void
- _M_move(_CharT* __d, const _CharT* __s, size_type __n) _GLIBCXX_NOEXCEPT
- {
- if (__n == 1)
- traits_type::assign(*__d, *__s);
- else
- traits_type::move(__d, __s, __n);
- }
-
- static void
- _M_assign(_CharT* __d, size_type __n, _CharT __c) _GLIBCXX_NOEXCEPT
- {
- if (__n == 1)
- traits_type::assign(*__d, __c);
- else
- traits_type::assign(__d, __n, __c);
- }
-
- // _S_copy_chars is a separate template to permit specialization
- // to optimize for the common case of pointers as iterators.
- template<class _Iterator>
- static void
- _S_copy_chars(_CharT* __p, _Iterator __k1, _Iterator __k2)
- {
- for (; __k1 != __k2; ++__k1, (void)++__p)
- traits_type::assign(*__p, *__k1); // These types are off.
- }
-
- static void
- _S_copy_chars(_CharT* __p, iterator __k1, iterator __k2) _GLIBCXX_NOEXCEPT
- { _S_copy_chars(__p, __k1.base(), __k2.base()); }
-
- static void
- _S_copy_chars(_CharT* __p, const_iterator __k1, const_iterator __k2)
- _GLIBCXX_NOEXCEPT
- { _S_copy_chars(__p, __k1.base(), __k2.base()); }
-
- static void
- _S_copy_chars(_CharT* __p, _CharT* __k1, _CharT* __k2) _GLIBCXX_NOEXCEPT
- { _M_copy(__p, __k1, __k2 - __k1); }
-
- static void
- _S_copy_chars(_CharT* __p, const _CharT* __k1, const _CharT* __k2)
- _GLIBCXX_NOEXCEPT
- { _M_copy(__p, __k1, __k2 - __k1); }
-
- static int
- _S_compare(size_type __n1, size_type __n2) _GLIBCXX_NOEXCEPT
- {
- const difference_type __d = difference_type(__n1 - __n2);
-
- if (__d > __gnu_cxx::__numeric_traits<int>::__max)
- return __gnu_cxx::__numeric_traits<int>::__max;
- else if (__d < __gnu_cxx::__numeric_traits<int>::__min)
- return __gnu_cxx::__numeric_traits<int>::__min;
- else
- return int(__d);
- }
-
- void
- _M_mutate(size_type __pos, size_type __len1, size_type __len2);
-
- void
- _M_leak_hard();
-
- static _Rep&
- _S_empty_rep() _GLIBCXX_NOEXCEPT
- { return _Rep::_S_empty_rep(); }
-
-#if __cplusplus >= 201703L
- // A helper type for avoiding boiler-plate.
- typedef basic_string_view<_CharT, _Traits> __sv_type;
-
- template<typename _Tp, typename _Res>
- using _If_sv = enable_if_t<
- __and_<is_convertible<const _Tp&, __sv_type>,
- __not_<is_convertible<const _Tp*, const basic_string*>>,
- __not_<is_convertible<const _Tp&, const _CharT*>>>::value,
- _Res>;
-
- // Allows an implicit conversion to __sv_type.
- static __sv_type
- _S_to_string_view(__sv_type __svt) noexcept
- { return __svt; }
-
- // Wraps a string_view by explicit conversion and thus
- // allows to add an internal constructor that does not
- // participate in overload resolution when a string_view
- // is provided.
- struct __sv_wrapper
- {
- explicit __sv_wrapper(__sv_type __sv) noexcept : _M_sv(__sv) { }
- __sv_type _M_sv;
- };
-
- /**
- * @brief Only internally used: Construct string from a string view
- * wrapper.
- * @param __svw string view wrapper.
- * @param __a Allocator to use.
- */
- explicit
- basic_string(__sv_wrapper __svw, const _Alloc& __a)
- : basic_string(__svw._M_sv.data(), __svw._M_sv.size(), __a) { }
-#endif
+_GLIBCXX_END_NAMESPACE_VERSION
+} // namespace std
+#endif // _GLIBCXX_USE_CXX11_ABI
- public:
- // Construct/copy/destroy:
- // NB: We overload ctors in some cases instead of using default
- // arguments, per 17.4.4.4 para. 2 item 2.
-
- /**
- * @brief Default constructor creates an empty string.
- */
- basic_string()
-#if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
- _GLIBCXX_NOEXCEPT
- : _M_dataplus(_S_empty_rep()._M_refdata(), _Alloc())
-#else
- : _M_dataplus(_S_construct(size_type(), _CharT(), _Alloc()), _Alloc())
-#endif
- { }
-
- /**
- * @brief Construct an empty string using allocator @a a.
- */
- explicit
- basic_string(const _Alloc& __a)
- : _M_dataplus(_S_construct(size_type(), _CharT(), __a), __a)
- { }
-
- // NB: per LWG issue 42, semantics different from IS:
- /**
- * @brief Construct string with copy of value of @a str.
- * @param __str Source string.
- */
- basic_string(const basic_string& __str)
- : _M_dataplus(__str._M_rep()->_M_grab(_Alloc(__str.get_allocator()),
- __str.get_allocator()),
- __str.get_allocator())
- { }
-
- // _GLIBCXX_RESOLVE_LIB_DEFECTS
- // 2583. no way to supply an allocator for basic_string(str, pos)
- /**
- * @brief Construct string as copy of a substring.
- * @param __str Source string.
- * @param __pos Index of first character to copy from.
- * @param __a Allocator to use.
- */
- basic_string(const basic_string& __str, size_type __pos,
- const _Alloc& __a = _Alloc());
-
- /**
- * @brief Construct string as copy of a substring.
- * @param __str Source string.
- * @param __pos Index of first character to copy from.
- * @param __n Number of characters to copy.
- */
- basic_string(const basic_string& __str, size_type __pos,
- size_type __n);
- /**
- * @brief Construct string as copy of a substring.
- * @param __str Source string.
- * @param __pos Index of first character to copy from.
- * @param __n Number of characters to copy.
- * @param __a Allocator to use.
- */
- basic_string(const basic_string& __str, size_type __pos,
- size_type __n, const _Alloc& __a);
-
- /**
- * @brief Construct string initialized by a character %array.
- * @param __s Source character %array.
- * @param __n Number of characters to copy.
- * @param __a Allocator to use (default is default allocator).
- *
- * NB: @a __s must have at least @a __n characters, '\\0'
- * has no special meaning.
- */
- basic_string(const _CharT* __s, size_type __n,
- const _Alloc& __a = _Alloc())
- : _M_dataplus(_S_construct(__s, __s + __n, __a), __a)
- { }
-
- /**
- * @brief Construct string as copy of a C string.
- * @param __s Source C string.
- * @param __a Allocator to use (default is default allocator).
- */
-#if __cpp_deduction_guides && ! defined _GLIBCXX_DEFINING_STRING_INSTANTIATIONS
- // _GLIBCXX_RESOLVE_LIB_DEFECTS
- // 3076. basic_string CTAD ambiguity
- template<typename = _RequireAllocator<_Alloc>>
-#endif
- basic_string(const _CharT* __s, const _Alloc& __a = _Alloc())
- : _M_dataplus(_S_construct(__s, __s ? __s + traits_type::length(__s) :
- __s + npos, __a), __a)
- { }
-
- /**
- * @brief Construct string as multiple characters.
- * @param __n Number of characters.
- * @param __c Character to use.
- * @param __a Allocator to use (default is default allocator).
- */
- basic_string(size_type __n, _CharT __c, const _Alloc& __a = _Alloc())
- : _M_dataplus(_S_construct(__n, __c, __a), __a)
- { }
-
-#if __cplusplus >= 201103L
- /**
- * @brief Move construct string.
- * @param __str Source string.
- *
- * The newly-created string contains the exact contents of @a __str.
- * @a __str is a valid, but unspecified string.
- */
- basic_string(basic_string&& __str)
-#if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
- noexcept // FIXME C++11: should always be noexcept.
-#endif
- : _M_dataplus(std::move(__str._M_dataplus))
- {
-#if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
- __str._M_data(_S_empty_rep()._M_refdata());
-#else
- __str._M_data(_S_construct(size_type(), _CharT(), get_allocator()));
-#endif
- }
-
- /**
- * @brief Construct string from an initializer %list.
- * @param __l std::initializer_list of characters.
- * @param __a Allocator to use (default is default allocator).
- */
- basic_string(initializer_list<_CharT> __l, const _Alloc& __a = _Alloc())
- : _M_dataplus(_S_construct(__l.begin(), __l.end(), __a), __a)
- { }
-
- basic_string(const basic_string& __str, const _Alloc& __a)
- : _M_dataplus(__str._M_rep()->_M_grab(__a, __str.get_allocator()), __a)
- { }
-
- basic_string(basic_string&& __str, const _Alloc& __a)
- : _M_dataplus(__str._M_data(), __a)
- {
- if (__a == __str.get_allocator())
- {
-#if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
- __str._M_data(_S_empty_rep()._M_refdata());
-#else
- __str._M_data(_S_construct(size_type(), _CharT(), __a));
-#endif
- }
- else
- _M_dataplus._M_p = _S_construct(__str.begin(), __str.end(), __a);
- }
-#endif // C++11
-
- /**
- * @brief Construct string as copy of a range.
- * @param __beg Start of range.
- * @param __end End of range.
- * @param __a Allocator to use (default is default allocator).
- */
- template<class _InputIterator>
- basic_string(_InputIterator __beg, _InputIterator __end,
- const _Alloc& __a = _Alloc())
- : _M_dataplus(_S_construct(__beg, __end, __a), __a)
- { }
-
-#if __cplusplus >= 201703L
- /**
- * @brief Construct string from a substring of a string_view.
- * @param __t Source object convertible to string view.
- * @param __pos The index of the first character to copy from __t.
- * @param __n The number of characters to copy from __t.
- * @param __a Allocator to use.
- */
- template<typename _Tp, typename = _If_sv<_Tp, void>>
- basic_string(const _Tp& __t, size_type __pos, size_type __n,
- const _Alloc& __a = _Alloc())
- : basic_string(_S_to_string_view(__t).substr(__pos, __n), __a) { }
-
- /**
- * @brief Construct string from a string_view.
- * @param __t Source object convertible to string view.
- * @param __a Allocator to use (default is default allocator).
- */
- template<typename _Tp, typename = _If_sv<_Tp, void>>
- explicit
- basic_string(const _Tp& __t, const _Alloc& __a = _Alloc())
- : basic_string(__sv_wrapper(_S_to_string_view(__t)), __a) { }
-#endif // C++17
-
- /**
- * @brief Destroy the string instance.
- */
- ~basic_string() _GLIBCXX_NOEXCEPT
- { _M_rep()->_M_dispose(this->get_allocator()); }
-
- /**
- * @brief Assign the value of @a str to this string.
- * @param __str Source string.
- */
- basic_string&
- operator=(const basic_string& __str)
- { return this->assign(__str); }
-
- /**
- * @brief Copy contents of @a s into this string.
- * @param __s Source null-terminated string.
- */
- basic_string&
- operator=(const _CharT* __s)
- { return this->assign(__s); }
-
- /**
- * @brief Set value to string of length 1.
- * @param __c Source character.
- *
- * Assigning to a character makes this string length 1 and
- * (*this)[0] == @a c.
- */
- basic_string&
- operator=(_CharT __c)
- {
- this->assign(1, __c);
- return *this;
- }
-
-#if __cplusplus >= 201103L
- /**
- * @brief Move assign the value of @a str to this string.
- * @param __str Source string.
- *
- * The contents of @a str are moved into this string (without copying).
- * @a str is a valid, but unspecified string.
- */
- basic_string&
- operator=(basic_string&& __str)
- _GLIBCXX_NOEXCEPT_IF(allocator_traits<_Alloc>::is_always_equal::value)
- {
- // NB: DR 1204.
- this->swap(__str);
- return *this;
- }
-
- /**
- * @brief Set value to string constructed from initializer %list.
- * @param __l std::initializer_list.
- */
- basic_string&
- operator=(initializer_list<_CharT> __l)
- {
- this->assign(__l.begin(), __l.size());
- return *this;
- }
-#endif // C++11
-
-#if __cplusplus >= 201703L
- /**
- * @brief Set value to string constructed from a string_view.
- * @param __svt An object convertible to string_view.
- */
- template<typename _Tp>
- _If_sv<_Tp, basic_string&>
- operator=(const _Tp& __svt)
- { return this->assign(__svt); }
-
- /**
- * @brief Convert to a string_view.
- * @return A string_view.
- */
- operator __sv_type() const noexcept
- { return __sv_type(data(), size()); }
-#endif // C++17
-
- // Iterators:
- /**
- * Returns a read/write iterator that points to the first character in
- * the %string. Unshares the string.
- */
- iterator
- begin() // FIXME C++11: should be noexcept.
- {
- _M_leak();
- return iterator(_M_data());
- }
-
- /**
- * Returns a read-only (constant) iterator that points to the first
- * character in the %string.
- */
- const_iterator
- begin() const _GLIBCXX_NOEXCEPT
- { return const_iterator(_M_data()); }
-
- /**
- * Returns a read/write iterator that points one past the last
- * character in the %string. Unshares the string.
- */
- iterator
- end() // FIXME C++11: should be noexcept.
- {
- _M_leak();
- return iterator(_M_data() + this->size());
- }
-
- /**
- * Returns a read-only (constant) iterator that points one past the
- * last character in the %string.
- */
- const_iterator
- end() const _GLIBCXX_NOEXCEPT
- { return const_iterator(_M_data() + this->size()); }
-
- /**
- * Returns a read/write reverse iterator that points to the last
- * character in the %string. Iteration is done in reverse element
- * order. Unshares the string.
- */
- reverse_iterator
- rbegin() // FIXME C++11: should be noexcept.
- { return reverse_iterator(this->end()); }
-
- /**
- * Returns a read-only (constant) reverse iterator that points
- * to the last character in the %string. Iteration is done in
- * reverse element order.
- */
- const_reverse_iterator
- rbegin() const _GLIBCXX_NOEXCEPT
- { return const_reverse_iterator(this->end()); }
-
- /**
- * Returns a read/write reverse iterator that points to one before the
- * first character in the %string. Iteration is done in reverse
- * element order. Unshares the string.
- */
- reverse_iterator
- rend() // FIXME C++11: should be noexcept.
- { return reverse_iterator(this->begin()); }
-
- /**
- * Returns a read-only (constant) reverse iterator that points
- * to one before the first character in the %string. Iteration
- * is done in reverse element order.
- */
- const_reverse_iterator
- rend() const _GLIBCXX_NOEXCEPT
- { return const_reverse_iterator(this->begin()); }
-
-#if __cplusplus >= 201103L
- /**
- * Returns a read-only (constant) iterator that points to the first
- * character in the %string.
- */
- const_iterator
- cbegin() const noexcept
- { return const_iterator(this->_M_data()); }
-
- /**
- * Returns a read-only (constant) iterator that points one past the
- * last character in the %string.
- */
- const_iterator
- cend() const noexcept
- { return const_iterator(this->_M_data() + this->size()); }
-
- /**
- * Returns a read-only (constant) reverse iterator that points
- * to the last character in the %string. Iteration is done in
- * reverse element order.
- */
- const_reverse_iterator
- crbegin() const noexcept
- { return const_reverse_iterator(this->end()); }
-
- /**
- * Returns a read-only (constant) reverse iterator that points
- * to one before the first character in the %string. Iteration
- * is done in reverse element order.
- */
- const_reverse_iterator
- crend() const noexcept
- { return const_reverse_iterator(this->begin()); }
-#endif
-
- public:
- // Capacity:
- /// Returns the number of characters in the string, not including any
- /// null-termination.
- size_type
- size() const _GLIBCXX_NOEXCEPT
- { return _M_rep()->_M_length; }
-
- /// Returns the number of characters in the string, not including any
- /// null-termination.
- size_type
- length() const _GLIBCXX_NOEXCEPT
- { return _M_rep()->_M_length; }
-
- /// Returns the size() of the largest possible %string.
- size_type
- max_size() const _GLIBCXX_NOEXCEPT
- { return _Rep::_S_max_size; }
-
- /**
- * @brief Resizes the %string to the specified number of characters.
- * @param __n Number of characters the %string should contain.
- * @param __c Character to fill any new elements.
- *
- * This function will %resize the %string to the specified
- * number of characters. If the number is smaller than the
- * %string's current size the %string is truncated, otherwise
- * the %string is extended and new elements are %set to @a __c.
- */
- void
- resize(size_type __n, _CharT __c);
-
- /**
- * @brief Resizes the %string to the specified number of characters.
- * @param __n Number of characters the %string should contain.
- *
- * This function will resize the %string to the specified length. If
- * the new size is smaller than the %string's current size the %string
- * is truncated, otherwise the %string is extended and new characters
- * are default-constructed. For basic types such as char, this means
- * setting them to 0.
- */
- void
- resize(size_type __n)
- { this->resize(__n, _CharT()); }
-
-#if __cplusplus >= 201103L
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
- /// A non-binding request to reduce capacity() to size().
- void
- shrink_to_fit() noexcept
- { reserve(); }
-#pragma GCC diagnostic pop
-#endif
-
- /**
- * Returns the total number of characters that the %string can hold
- * before needing to allocate more memory.
- */
- size_type
- capacity() const _GLIBCXX_NOEXCEPT
- { return _M_rep()->_M_capacity; }
-
- /**
- * @brief Attempt to preallocate enough memory for specified number of
- * characters.
- * @param __res_arg Number of characters required.
- * @throw std::length_error If @a __res_arg exceeds @c max_size().
- *
- * This function attempts to reserve enough memory for the
- * %string to hold the specified number of characters. If the
- * number requested is more than max_size(), length_error is
- * thrown.
- *
- * The advantage of this function is that if optimal code is a
- * necessity and the user can determine the string length that will be
- * required, the user can reserve the memory in %advance, and thus
- * prevent a possible reallocation of memory and copying of %string
- * data.
- */
- void
- reserve(size_type __res_arg);
-
- /// Equivalent to shrink_to_fit().
-#if __cplusplus > 201703L
- [[deprecated("use shrink_to_fit() instead")]]
-#endif
- void
- reserve();
-
- /**
- * Erases the string, making it empty.
- */
-#if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
- void
- clear() _GLIBCXX_NOEXCEPT
- {
- if (_M_rep()->_M_is_shared())
- {
- _M_rep()->_M_dispose(this->get_allocator());
- _M_data(_S_empty_rep()._M_refdata());
- }
- else
- _M_rep()->_M_set_length_and_sharable(0);
- }
-#else
- // PR 56166: this should not throw.
- void
- clear()
- { _M_mutate(0, this->size(), 0); }
-#endif
-
- /**
- * Returns true if the %string is empty. Equivalent to
- * <code>*this == ""</code>.
- */
- _GLIBCXX_NODISCARD bool
- empty() const _GLIBCXX_NOEXCEPT
- { return this->size() == 0; }
-
- // Element access:
- /**
- * @brief Subscript access to the data contained in the %string.
- * @param __pos The index of the character to access.
- * @return Read-only (constant) reference to the character.
- *
- * This operator allows for easy, array-style, data access.
- * Note that data access with this operator is unchecked and
- * out_of_range lookups are not defined. (For checked lookups
- * see at().)
- */
- const_reference
- operator[] (size_type __pos) const _GLIBCXX_NOEXCEPT
- {
- __glibcxx_assert(__pos <= size());
- return _M_data()[__pos];
- }
-
- /**
- * @brief Subscript access to the data contained in the %string.
- * @param __pos The index of the character to access.
- * @return Read/write reference to the character.
- *
- * This operator allows for easy, array-style, data access.
- * Note that data access with this operator is unchecked and
- * out_of_range lookups are not defined. (For checked lookups
- * see at().) Unshares the string.
- */
- reference
- operator[](size_type __pos)
- {
- // Allow pos == size() both in C++98 mode, as v3 extension,
- // and in C++11 mode.
- __glibcxx_assert(__pos <= size());
- // In pedantic mode be strict in C++98 mode.
- _GLIBCXX_DEBUG_PEDASSERT(__cplusplus >= 201103L || __pos < size());
- _M_leak();
- return _M_data()[__pos];
- }
-
- /**
- * @brief Provides access to the data contained in the %string.
- * @param __n The index of the character to access.
- * @return Read-only (const) reference to the character.
- * @throw std::out_of_range If @a n is an invalid index.
- *
- * This function provides for safer data access. The parameter is
- * first checked that it is in the range of the string. The function
- * throws out_of_range if the check fails.
- */
- const_reference
- at(size_type __n) const
- {
- if (__n >= this->size())
- __throw_out_of_range_fmt(__N("basic_string::at: __n "
- "(which is %zu) >= this->size() "
- "(which is %zu)"),
- __n, this->size());
- return _M_data()[__n];
- }
-
- /**
- * @brief Provides access to the data contained in the %string.
- * @param __n The index of the character to access.
- * @return Read/write reference to the character.
- * @throw std::out_of_range If @a n is an invalid index.
- *
- * This function provides for safer data access. The parameter is
- * first checked that it is in the range of the string. The function
- * throws out_of_range if the check fails. Success results in
- * unsharing the string.
- */
- reference
- at(size_type __n)
- {
- if (__n >= size())
- __throw_out_of_range_fmt(__N("basic_string::at: __n "
- "(which is %zu) >= this->size() "
- "(which is %zu)"),
- __n, this->size());
- _M_leak();
- return _M_data()[__n];
- }
-
-#if __cplusplus >= 201103L
- /**
- * Returns a read/write reference to the data at the first
- * element of the %string.
- */
- reference
- front()
- {
- __glibcxx_assert(!empty());
- return operator[](0);
- }
-
- /**
- * Returns a read-only (constant) reference to the data at the first
- * element of the %string.
- */
- const_reference
- front() const noexcept
- {
- __glibcxx_assert(!empty());
- return operator[](0);
- }
-
- /**
- * Returns a read/write reference to the data at the last
- * element of the %string.
- */
- reference
- back()
- {
- __glibcxx_assert(!empty());
- return operator[](this->size() - 1);
- }
-
- /**
- * Returns a read-only (constant) reference to the data at the
- * last element of the %string.
- */
- const_reference
- back() const noexcept
- {
- __glibcxx_assert(!empty());
- return operator[](this->size() - 1);
- }
-#endif
-
- // Modifiers:
- /**
- * @brief Append a string to this string.
- * @param __str The string to append.
- * @return Reference to this string.
- */
- basic_string&
- operator+=(const basic_string& __str)
- { return this->append(__str); }
-
- /**
- * @brief Append a C string.
- * @param __s The C string to append.
- * @return Reference to this string.
- */
- basic_string&
- operator+=(const _CharT* __s)
- { return this->append(__s); }
-
- /**
- * @brief Append a character.
- * @param __c The character to append.
- * @return Reference to this string.
- */
- basic_string&
- operator+=(_CharT __c)
- {
- this->push_back(__c);
- return *this;
- }
-
-#if __cplusplus >= 201103L
- /**
- * @brief Append an initializer_list of characters.
- * @param __l The initializer_list of characters to be appended.
- * @return Reference to this string.
- */
- basic_string&
- operator+=(initializer_list<_CharT> __l)
- { return this->append(__l.begin(), __l.size()); }
-#endif // C++11
-
-#if __cplusplus >= 201703L
- /**
- * @brief Append a string_view.
- * @param __svt The object convertible to string_view to be appended.
- * @return Reference to this string.
- */
- template<typename _Tp>
- _If_sv<_Tp, basic_string&>
- operator+=(const _Tp& __svt)
- { return this->append(__svt); }
-#endif // C++17
-
- /**
- * @brief Append a string to this string.
- * @param __str The string to append.
- * @return Reference to this string.
- */
- basic_string&
- append(const basic_string& __str);
-
- /**
- * @brief Append a substring.
- * @param __str The string to append.
- * @param __pos Index of the first character of str to append.
- * @param __n The number of characters to append.
- * @return Reference to this string.
- * @throw std::out_of_range if @a __pos is not a valid index.
- *
- * This function appends @a __n characters from @a __str
- * starting at @a __pos to this string. If @a __n is is larger
- * than the number of available characters in @a __str, the
- * remainder of @a __str is appended.
- */
- basic_string&
- append(const basic_string& __str, size_type __pos, size_type __n = npos);
-
- /**
- * @brief Append a C substring.
- * @param __s The C string to append.
- * @param __n The number of characters to append.
- * @return Reference to this string.
- */
- basic_string&
- append(const _CharT* __s, size_type __n);
-
- /**
- * @brief Append a C string.
- * @param __s The C string to append.
- * @return Reference to this string.
- */
- basic_string&
- append(const _CharT* __s)
- {
- __glibcxx_requires_string(__s);
- return this->append(__s, traits_type::length(__s));
- }
-
- /**
- * @brief Append multiple characters.
- * @param __n The number of characters to append.
- * @param __c The character to use.
- * @return Reference to this string.
- *
- * Appends __n copies of __c to this string.
- */
- basic_string&
- append(size_type __n, _CharT __c);
-
-#if __cplusplus >= 201103L
- /**
- * @brief Append an initializer_list of characters.
- * @param __l The initializer_list of characters to append.
- * @return Reference to this string.
- */
- basic_string&
- append(initializer_list<_CharT> __l)
- { return this->append(__l.begin(), __l.size()); }
-#endif // C++11
-
- /**
- * @brief Append a range of characters.
- * @param __first Iterator referencing the first character to append.
- * @param __last Iterator marking the end of the range.
- * @return Reference to this string.
- *
- * Appends characters in the range [__first,__last) to this string.
- */
- template<class _InputIterator>
- basic_string&
- append(_InputIterator __first, _InputIterator __last)
- { return this->replace(_M_iend(), _M_iend(), __first, __last); }
-
-#if __cplusplus >= 201703L
- /**
- * @brief Append a string_view.
- * @param __svt The object convertible to string_view to be appended.
- * @return Reference to this string.
- */
- template<typename _Tp>
- _If_sv<_Tp, basic_string&>
- append(const _Tp& __svt)
- {
- __sv_type __sv = __svt;
- return this->append(__sv.data(), __sv.size());
- }
-
- /**
- * @brief Append a range of characters from a string_view.
- * @param __svt The object convertible to string_view to be appended
- * from.
- * @param __pos The position in the string_view to append from.
- * @param __n The number of characters to append from the string_view.
- * @return Reference to this string.
- */
- template<typename _Tp>
- _If_sv<_Tp, basic_string&>
- append(const _Tp& __svt, size_type __pos, size_type __n = npos)
- {
- __sv_type __sv = __svt;
- return append(__sv.data()
- + std::__sv_check(__sv.size(), __pos, "basic_string::append"),
- std::__sv_limit(__sv.size(), __pos, __n));
- }
-#endif // C++17
-
- /**
- * @brief Append a single character.
- * @param __c Character to append.
- */
- void
- push_back(_CharT __c)
- {
- const size_type __len = 1 + this->size();
- if (__len > this->capacity() || _M_rep()->_M_is_shared())
- this->reserve(__len);
- traits_type::assign(_M_data()[this->size()], __c);
- _M_rep()->_M_set_length_and_sharable(__len);
- }
-
- /**
- * @brief Set value to contents of another string.
- * @param __str Source string to use.
- * @return Reference to this string.
- */
- basic_string&
- assign(const basic_string& __str);
-
-#if __cplusplus >= 201103L
- /**
- * @brief Set value to contents of another string.
- * @param __str Source string to use.
- * @return Reference to this string.
- *
- * This function sets this string to the exact contents of @a __str.
- * @a __str is a valid, but unspecified string.
- */
- basic_string&
- assign(basic_string&& __str)
- noexcept(allocator_traits<_Alloc>::is_always_equal::value)
- {
- this->swap(__str);
- return *this;
- }
-#endif // C++11
-
- /**
- * @brief Set value to a substring of a string.
- * @param __str The string to use.
- * @param __pos Index of the first character of str.
- * @param __n Number of characters to use.
- * @return Reference to this string.
- * @throw std::out_of_range if @a pos is not a valid index.
- *
- * This function sets this string to the substring of @a __str
- * consisting of @a __n characters at @a __pos. If @a __n is
- * is larger than the number of available characters in @a
- * __str, the remainder of @a __str is used.
- */
- basic_string&
- assign(const basic_string& __str, size_type __pos, size_type __n = npos)
- { return this->assign(__str._M_data()
- + __str._M_check(__pos, "basic_string::assign"),
- __str._M_limit(__pos, __n)); }
-
- /**
- * @brief Set value to a C substring.
- * @param __s The C string to use.
- * @param __n Number of characters to use.
- * @return Reference to this string.
- *
- * This function sets the value of this string to the first @a __n
- * characters of @a __s. If @a __n is is larger than the number of
- * available characters in @a __s, the remainder of @a __s is used.
- */
- basic_string&
- assign(const _CharT* __s, size_type __n);
-
- /**
- * @brief Set value to contents of a C string.
- * @param __s The C string to use.
- * @return Reference to this string.
- *
- * This function sets the value of this string to the value of @a __s.
- * The data is copied, so there is no dependence on @a __s once the
- * function returns.
- */
- basic_string&
- assign(const _CharT* __s)
- {
- __glibcxx_requires_string(__s);
- return this->assign(__s, traits_type::length(__s));
- }
-
- /**
- * @brief Set value to multiple characters.
- * @param __n Length of the resulting string.
- * @param __c The character to use.
- * @return Reference to this string.
- *
- * This function sets the value of this string to @a __n copies of
- * character @a __c.
- */
- basic_string&
- assign(size_type __n, _CharT __c)
- { return _M_replace_aux(size_type(0), this->size(), __n, __c); }
-
- /**
- * @brief Set value to a range of characters.
- * @param __first Iterator referencing the first character to append.
- * @param __last Iterator marking the end of the range.
- * @return Reference to this string.
- *
- * Sets value of string to characters in the range [__first,__last).
- */
- template<class _InputIterator>
- basic_string&
- assign(_InputIterator __first, _InputIterator __last)
- { return this->replace(_M_ibegin(), _M_iend(), __first, __last); }
-
-#if __cplusplus >= 201103L
- /**
- * @brief Set value to an initializer_list of characters.
- * @param __l The initializer_list of characters to assign.
- * @return Reference to this string.
- */
- basic_string&
- assign(initializer_list<_CharT> __l)
- { return this->assign(__l.begin(), __l.size()); }
-#endif // C++11
-
-#if __cplusplus >= 201703L
- /**
- * @brief Set value from a string_view.
- * @param __svt The source object convertible to string_view.
- * @return Reference to this string.
- */
- template<typename _Tp>
- _If_sv<_Tp, basic_string&>
- assign(const _Tp& __svt)
- {
- __sv_type __sv = __svt;
- return this->assign(__sv.data(), __sv.size());
- }
-
- /**
- * @brief Set value from a range of characters in a string_view.
- * @param __svt The source object convertible to string_view.
- * @param __pos The position in the string_view to assign from.
- * @param __n The number of characters to assign.
- * @return Reference to this string.
- */
- template<typename _Tp>
- _If_sv<_Tp, basic_string&>
- assign(const _Tp& __svt, size_type __pos, size_type __n = npos)
- {
- __sv_type __sv = __svt;
- return assign(__sv.data()
- + std::__sv_check(__sv.size(), __pos, "basic_string::assign"),
- std::__sv_limit(__sv.size(), __pos, __n));
- }
-#endif // C++17
-
- /**
- * @brief Insert multiple characters.
- * @param __p Iterator referencing location in string to insert at.
- * @param __n Number of characters to insert
- * @param __c The character to insert.
- * @throw std::length_error If new length exceeds @c max_size().
- *
- * Inserts @a __n copies of character @a __c starting at the
- * position referenced by iterator @a __p. If adding
- * characters causes the length to exceed max_size(),
- * length_error is thrown. The value of the string doesn't
- * change if an error is thrown.
- */
- void
- insert(iterator __p, size_type __n, _CharT __c)
- { this->replace(__p, __p, __n, __c); }
-
- /**
- * @brief Insert a range of characters.
- * @param __p Iterator referencing location in string to insert at.
- * @param __beg Start of range.
- * @param __end End of range.
- * @throw std::length_error If new length exceeds @c max_size().
- *
- * Inserts characters in range [__beg,__end). If adding
- * characters causes the length to exceed max_size(),
- * length_error is thrown. The value of the string doesn't
- * change if an error is thrown.
- */
- template<class _InputIterator>
- void
- insert(iterator __p, _InputIterator __beg, _InputIterator __end)
- { this->replace(__p, __p, __beg, __end); }
-
-#if __cplusplus >= 201103L
- /**
- * @brief Insert an initializer_list of characters.
- * @param __p Iterator referencing location in string to insert at.
- * @param __l The initializer_list of characters to insert.
- * @throw std::length_error If new length exceeds @c max_size().
- */
- void
- insert(iterator __p, initializer_list<_CharT> __l)
- {
- _GLIBCXX_DEBUG_PEDASSERT(__p >= _M_ibegin() && __p <= _M_iend());
- this->insert(__p - _M_ibegin(), __l.begin(), __l.size());
- }
-#endif // C++11
-
- /**
- * @brief Insert value of a string.
- * @param __pos1 Position in string to insert at.
- * @param __str The string to insert.
- * @return Reference to this string.
- * @throw std::length_error If new length exceeds @c max_size().
- *
- * Inserts value of @a __str starting at @a __pos1. If adding
- * characters causes the length to exceed max_size(),
- * length_error is thrown. The value of the string doesn't
- * change if an error is thrown.
- */
- basic_string&
- insert(size_type __pos1, const basic_string& __str)
- { return this->insert(__pos1, __str, size_type(0), __str.size()); }
-
- /**
- * @brief Insert a substring.
- * @param __pos1 Position in string to insert at.
- * @param __str The string to insert.
- * @param __pos2 Start of characters in str to insert.
- * @param __n Number of characters to insert.
- * @return Reference to this string.
- * @throw std::length_error If new length exceeds @c max_size().
- * @throw std::out_of_range If @a pos1 > size() or
- * @a __pos2 > @a str.size().
- *
- * Starting at @a pos1, insert @a __n character of @a __str
- * beginning with @a __pos2. If adding characters causes the
- * length to exceed max_size(), length_error is thrown. If @a
- * __pos1 is beyond the end of this string or @a __pos2 is
- * beyond the end of @a __str, out_of_range is thrown. The
- * value of the string doesn't change if an error is thrown.
- */
- basic_string&
- insert(size_type __pos1, const basic_string& __str,
- size_type __pos2, size_type __n = npos)
- { return this->insert(__pos1, __str._M_data()
- + __str._M_check(__pos2, "basic_string::insert"),
- __str._M_limit(__pos2, __n)); }
-
- /**
- * @brief Insert a C substring.
- * @param __pos Position in string to insert at.
- * @param __s The C string to insert.
- * @param __n The number of characters to insert.
- * @return Reference to this string.
- * @throw std::length_error If new length exceeds @c max_size().
- * @throw std::out_of_range If @a __pos is beyond the end of this
- * string.
- *
- * Inserts the first @a __n characters of @a __s starting at @a
- * __pos. If adding characters causes the length to exceed
- * max_size(), length_error is thrown. If @a __pos is beyond
- * end(), out_of_range is thrown. The value of the string
- * doesn't change if an error is thrown.
- */
- basic_string&
- insert(size_type __pos, const _CharT* __s, size_type __n);
-
- /**
- * @brief Insert a C string.
- * @param __pos Position in string to insert at.
- * @param __s The C string to insert.
- * @return Reference to this string.
- * @throw std::length_error If new length exceeds @c max_size().
- * @throw std::out_of_range If @a pos is beyond the end of this
- * string.
- *
- * Inserts the first @a n characters of @a __s starting at @a __pos. If
- * adding characters causes the length to exceed max_size(),
- * length_error is thrown. If @a __pos is beyond end(), out_of_range is
- * thrown. The value of the string doesn't change if an error is
- * thrown.
- */
- basic_string&
- insert(size_type __pos, const _CharT* __s)
- {
- __glibcxx_requires_string(__s);
- return this->insert(__pos, __s, traits_type::length(__s));
- }
-
- /**
- * @brief Insert multiple characters.
- * @param __pos Index in string to insert at.
- * @param __n Number of characters to insert
- * @param __c The character to insert.
- * @return Reference to this string.
- * @throw std::length_error If new length exceeds @c max_size().
- * @throw std::out_of_range If @a __pos is beyond the end of this
- * string.
- *
- * Inserts @a __n copies of character @a __c starting at index
- * @a __pos. If adding characters causes the length to exceed
- * max_size(), length_error is thrown. If @a __pos > length(),
- * out_of_range is thrown. The value of the string doesn't
- * change if an error is thrown.
- */
- basic_string&
- insert(size_type __pos, size_type __n, _CharT __c)
- { return _M_replace_aux(_M_check(__pos, "basic_string::insert"),
- size_type(0), __n, __c); }
-
- /**
- * @brief Insert one character.
- * @param __p Iterator referencing position in string to insert at.
- * @param __c The character to insert.
- * @return Iterator referencing newly inserted char.
- * @throw std::length_error If new length exceeds @c max_size().
- *
- * Inserts character @a __c at position referenced by @a __p.
- * If adding character causes the length to exceed max_size(),
- * length_error is thrown. If @a __p is beyond end of string,
- * out_of_range is thrown. The value of the string doesn't
- * change if an error is thrown.
- */
- iterator
- insert(iterator __p, _CharT __c)
- {
- _GLIBCXX_DEBUG_PEDASSERT(__p >= _M_ibegin() && __p <= _M_iend());
- const size_type __pos = __p - _M_ibegin();
- _M_replace_aux(__pos, size_type(0), size_type(1), __c);
- _M_rep()->_M_set_leaked();
- return iterator(_M_data() + __pos);
- }
-
-#if __cplusplus >= 201703L
- /**
- * @brief Insert a string_view.
- * @param __pos Position in string to insert at.
- * @param __svt The object convertible to string_view to insert.
- * @return Reference to this string.
- */
- template<typename _Tp>
- _If_sv<_Tp, basic_string&>
- insert(size_type __pos, const _Tp& __svt)
- {
- __sv_type __sv = __svt;
- return this->insert(__pos, __sv.data(), __sv.size());
- }
-
- /**
- * @brief Insert a string_view.
- * @param __pos1 Position in string to insert at.
- * @param __svt The object convertible to string_view to insert from.
- * @param __pos2 Position in string_view to insert from.
- * @param __n The number of characters to insert.
- * @return Reference to this string.
- */
- template<typename _Tp>
- _If_sv<_Tp, basic_string&>
- insert(size_type __pos1, const _Tp& __svt,
- size_type __pos2, size_type __n = npos)
- {
- __sv_type __sv = __svt;
- return this->replace(__pos1, size_type(0), __sv.data()
- + std::__sv_check(__sv.size(), __pos2, "basic_string::insert"),
- std::__sv_limit(__sv.size(), __pos2, __n));
- }
-#endif // C++17
-
- /**
- * @brief Remove characters.
- * @param __pos Index of first character to remove (default 0).
- * @param __n Number of characters to remove (default remainder).
- * @return Reference to this string.
- * @throw std::out_of_range If @a pos is beyond the end of this
- * string.
- *
- * Removes @a __n characters from this string starting at @a
- * __pos. The length of the string is reduced by @a __n. If
- * there are < @a __n characters to remove, the remainder of
- * the string is truncated. If @a __p is beyond end of string,
- * out_of_range is thrown. The value of the string doesn't
- * change if an error is thrown.
- */
- basic_string&
- erase(size_type __pos = 0, size_type __n = npos)
- {
- _M_mutate(_M_check(__pos, "basic_string::erase"),
- _M_limit(__pos, __n), size_type(0));
- return *this;
- }
-
- /**
- * @brief Remove one character.
- * @param __position Iterator referencing the character to remove.
- * @return iterator referencing same location after removal.
- *
- * Removes the character at @a __position from this string. The value
- * of the string doesn't change if an error is thrown.
- */
- iterator
- erase(iterator __position)
- {
- _GLIBCXX_DEBUG_PEDASSERT(__position >= _M_ibegin()
- && __position < _M_iend());
- const size_type __pos = __position - _M_ibegin();
- _M_mutate(__pos, size_type(1), size_type(0));
- _M_rep()->_M_set_leaked();
- return iterator(_M_data() + __pos);
- }
-
- /**
- * @brief Remove a range of characters.
- * @param __first Iterator referencing the first character to remove.
- * @param __last Iterator referencing the end of the range.
- * @return Iterator referencing location of first after removal.
- *
- * Removes the characters in the range [first,last) from this string.
- * The value of the string doesn't change if an error is thrown.
- */
- iterator
- erase(iterator __first, iterator __last);
-
-#if __cplusplus >= 201103L
- /**
- * @brief Remove the last character.
- *
- * The string must be non-empty.
- */
- void
- pop_back() // FIXME C++11: should be noexcept.
- {
- __glibcxx_assert(!empty());
- erase(size() - 1, 1);
- }
-#endif // C++11
-
- /**
- * @brief Replace characters with value from another string.
- * @param __pos Index of first character to replace.
- * @param __n Number of characters to be replaced.
- * @param __str String to insert.
- * @return Reference to this string.
- * @throw std::out_of_range If @a pos is beyond the end of this
- * string.
- * @throw std::length_error If new length exceeds @c max_size().
- *
- * Removes the characters in the range [__pos,__pos+__n) from
- * this string. In place, the value of @a __str is inserted.
- * If @a __pos is beyond end of string, out_of_range is thrown.
- * If the length of the result exceeds max_size(), length_error
- * is thrown. The value of the string doesn't change if an
- * error is thrown.
- */
- basic_string&
- replace(size_type __pos, size_type __n, const basic_string& __str)
- { return this->replace(__pos, __n, __str._M_data(), __str.size()); }
-
- /**
- * @brief Replace characters with value from another string.
- * @param __pos1 Index of first character to replace.
- * @param __n1 Number of characters to be replaced.
- * @param __str String to insert.
- * @param __pos2 Index of first character of str to use.
- * @param __n2 Number of characters from str to use.
- * @return Reference to this string.
- * @throw std::out_of_range If @a __pos1 > size() or @a __pos2 >
- * __str.size().
- * @throw std::length_error If new length exceeds @c max_size().
- *
- * Removes the characters in the range [__pos1,__pos1 + n) from this
- * string. In place, the value of @a __str is inserted. If @a __pos is
- * beyond end of string, out_of_range is thrown. If the length of the
- * result exceeds max_size(), length_error is thrown. The value of the
- * string doesn't change if an error is thrown.
- */
- basic_string&
- replace(size_type __pos1, size_type __n1, const basic_string& __str,
- size_type __pos2, size_type __n2 = npos)
- { return this->replace(__pos1, __n1, __str._M_data()
- + __str._M_check(__pos2, "basic_string::replace"),
- __str._M_limit(__pos2, __n2)); }
-
- /**
- * @brief Replace characters with value of a C substring.
- * @param __pos Index of first character to replace.
- * @param __n1 Number of characters to be replaced.
- * @param __s C string to insert.
- * @param __n2 Number of characters from @a s to use.
- * @return Reference to this string.
- * @throw std::out_of_range If @a pos1 > size().
- * @throw std::length_error If new length exceeds @c max_size().
- *
- * Removes the characters in the range [__pos,__pos + __n1)
- * from this string. In place, the first @a __n2 characters of
- * @a __s are inserted, or all of @a __s if @a __n2 is too large. If
- * @a __pos is beyond end of string, out_of_range is thrown. If
- * the length of result exceeds max_size(), length_error is
- * thrown. The value of the string doesn't change if an error
- * is thrown.
- */
- basic_string&
- replace(size_type __pos, size_type __n1, const _CharT* __s,
- size_type __n2);
-
- /**
- * @brief Replace characters with value of a C string.
- * @param __pos Index of first character to replace.
- * @param __n1 Number of characters to be replaced.
- * @param __s C string to insert.
- * @return Reference to this string.
- * @throw std::out_of_range If @a pos > size().
- * @throw std::length_error If new length exceeds @c max_size().
- *
- * Removes the characters in the range [__pos,__pos + __n1)
- * from this string. In place, the characters of @a __s are
- * inserted. If @a __pos is beyond end of string, out_of_range
- * is thrown. If the length of result exceeds max_size(),
- * length_error is thrown. The value of the string doesn't
- * change if an error is thrown.
- */
- basic_string&
- replace(size_type __pos, size_type __n1, const _CharT* __s)
- {
- __glibcxx_requires_string(__s);
- return this->replace(__pos, __n1, __s, traits_type::length(__s));
- }
-
- /**
- * @brief Replace characters with multiple characters.
- * @param __pos Index of first character to replace.
- * @param __n1 Number of characters to be replaced.
- * @param __n2 Number of characters to insert.
- * @param __c Character to insert.
- * @return Reference to this string.
- * @throw std::out_of_range If @a __pos > size().
- * @throw std::length_error If new length exceeds @c max_size().
- *
- * Removes the characters in the range [pos,pos + n1) from this
- * string. In place, @a __n2 copies of @a __c are inserted.
- * If @a __pos is beyond end of string, out_of_range is thrown.
- * If the length of result exceeds max_size(), length_error is
- * thrown. The value of the string doesn't change if an error
- * is thrown.
- */
- basic_string&
- replace(size_type __pos, size_type __n1, size_type __n2, _CharT __c)
- { return _M_replace_aux(_M_check(__pos, "basic_string::replace"),
- _M_limit(__pos, __n1), __n2, __c); }
-
- /**
- * @brief Replace range of characters with string.
- * @param __i1 Iterator referencing start of range to replace.
- * @param __i2 Iterator referencing end of range to replace.
- * @param __str String value to insert.
- * @return Reference to this string.
- * @throw std::length_error If new length exceeds @c max_size().
- *
- * Removes the characters in the range [__i1,__i2). In place,
- * the value of @a __str is inserted. If the length of result
- * exceeds max_size(), length_error is thrown. The value of
- * the string doesn't change if an error is thrown.
- */
- basic_string&
- replace(iterator __i1, iterator __i2, const basic_string& __str)
- { return this->replace(__i1, __i2, __str._M_data(), __str.size()); }
-
- /**
- * @brief Replace range of characters with C substring.
- * @param __i1 Iterator referencing start of range to replace.
- * @param __i2 Iterator referencing end of range to replace.
- * @param __s C string value to insert.
- * @param __n Number of characters from s to insert.
- * @return Reference to this string.
- * @throw std::length_error If new length exceeds @c max_size().
- *
- * Removes the characters in the range [__i1,__i2). In place,
- * the first @a __n characters of @a __s are inserted. If the
- * length of result exceeds max_size(), length_error is thrown.
- * The value of the string doesn't change if an error is
- * thrown.
- */
- basic_string&
- replace(iterator __i1, iterator __i2, const _CharT* __s, size_type __n)
- {
- _GLIBCXX_DEBUG_PEDASSERT(_M_ibegin() <= __i1 && __i1 <= __i2
- && __i2 <= _M_iend());
- return this->replace(__i1 - _M_ibegin(), __i2 - __i1, __s, __n);
- }
-
- /**
- * @brief Replace range of characters with C string.
- * @param __i1 Iterator referencing start of range to replace.
- * @param __i2 Iterator referencing end of range to replace.
- * @param __s C string value to insert.
- * @return Reference to this string.
- * @throw std::length_error If new length exceeds @c max_size().
- *
- * Removes the characters in the range [__i1,__i2). In place,
- * the characters of @a __s are inserted. If the length of
- * result exceeds max_size(), length_error is thrown. The
- * value of the string doesn't change if an error is thrown.
- */
- basic_string&
- replace(iterator __i1, iterator __i2, const _CharT* __s)
- {
- __glibcxx_requires_string(__s);
- return this->replace(__i1, __i2, __s, traits_type::length(__s));
- }
-
- /**
- * @brief Replace range of characters with multiple characters
- * @param __i1 Iterator referencing start of range to replace.
- * @param __i2 Iterator referencing end of range to replace.
- * @param __n Number of characters to insert.
- * @param __c Character to insert.
- * @return Reference to this string.
- * @throw std::length_error If new length exceeds @c max_size().
- *
- * Removes the characters in the range [__i1,__i2). In place,
- * @a __n copies of @a __c are inserted. If the length of
- * result exceeds max_size(), length_error is thrown. The
- * value of the string doesn't change if an error is thrown.
- */
- basic_string&
- replace(iterator __i1, iterator __i2, size_type __n, _CharT __c)
- {
- _GLIBCXX_DEBUG_PEDASSERT(_M_ibegin() <= __i1 && __i1 <= __i2
- && __i2 <= _M_iend());
- return _M_replace_aux(__i1 - _M_ibegin(), __i2 - __i1, __n, __c);
- }
-
- /**
- * @brief Replace range of characters with range.
- * @param __i1 Iterator referencing start of range to replace.
- * @param __i2 Iterator referencing end of range to replace.
- * @param __k1 Iterator referencing start of range to insert.
- * @param __k2 Iterator referencing end of range to insert.
- * @return Reference to this string.
- * @throw std::length_error If new length exceeds @c max_size().
- *
- * Removes the characters in the range [__i1,__i2). In place,
- * characters in the range [__k1,__k2) are inserted. If the
- * length of result exceeds max_size(), length_error is thrown.
- * The value of the string doesn't change if an error is
- * thrown.
- */
- template<class _InputIterator>
- basic_string&
- replace(iterator __i1, iterator __i2,
- _InputIterator __k1, _InputIterator __k2)
- {
- _GLIBCXX_DEBUG_PEDASSERT(_M_ibegin() <= __i1 && __i1 <= __i2
- && __i2 <= _M_iend());
- __glibcxx_requires_valid_range(__k1, __k2);
- typedef typename std::__is_integer<_InputIterator>::__type _Integral;
- return _M_replace_dispatch(__i1, __i2, __k1, __k2, _Integral());
- }
-
- // Specializations for the common case of pointer and iterator:
- // useful to avoid the overhead of temporary buffering in _M_replace.
- basic_string&
- replace(iterator __i1, iterator __i2, _CharT* __k1, _CharT* __k2)
- {
- _GLIBCXX_DEBUG_PEDASSERT(_M_ibegin() <= __i1 && __i1 <= __i2
- && __i2 <= _M_iend());
- __glibcxx_requires_valid_range(__k1, __k2);
- return this->replace(__i1 - _M_ibegin(), __i2 - __i1,
- __k1, __k2 - __k1);
- }
-
- basic_string&
- replace(iterator __i1, iterator __i2,
- const _CharT* __k1, const _CharT* __k2)
- {
- _GLIBCXX_DEBUG_PEDASSERT(_M_ibegin() <= __i1 && __i1 <= __i2
- && __i2 <= _M_iend());
- __glibcxx_requires_valid_range(__k1, __k2);
- return this->replace(__i1 - _M_ibegin(), __i2 - __i1,
- __k1, __k2 - __k1);
- }
-
- basic_string&
- replace(iterator __i1, iterator __i2, iterator __k1, iterator __k2)
- {
- _GLIBCXX_DEBUG_PEDASSERT(_M_ibegin() <= __i1 && __i1 <= __i2
- && __i2 <= _M_iend());
- __glibcxx_requires_valid_range(__k1, __k2);
- return this->replace(__i1 - _M_ibegin(), __i2 - __i1,
- __k1.base(), __k2 - __k1);
- }
-
- basic_string&
- replace(iterator __i1, iterator __i2,
- const_iterator __k1, const_iterator __k2)
- {
- _GLIBCXX_DEBUG_PEDASSERT(_M_ibegin() <= __i1 && __i1 <= __i2
- && __i2 <= _M_iend());
- __glibcxx_requires_valid_range(__k1, __k2);
- return this->replace(__i1 - _M_ibegin(), __i2 - __i1,
- __k1.base(), __k2 - __k1);
- }
-
-#if __cplusplus >= 201103L
- /**
- * @brief Replace range of characters with initializer_list.
- * @param __i1 Iterator referencing start of range to replace.
- * @param __i2 Iterator referencing end of range to replace.
- * @param __l The initializer_list of characters to insert.
- * @return Reference to this string.
- * @throw std::length_error If new length exceeds @c max_size().
- *
- * Removes the characters in the range [__i1,__i2). In place,
- * characters in the range [__k1,__k2) are inserted. If the
- * length of result exceeds max_size(), length_error is thrown.
- * The value of the string doesn't change if an error is
- * thrown.
- */
- basic_string& replace(iterator __i1, iterator __i2,
- initializer_list<_CharT> __l)
- { return this->replace(__i1, __i2, __l.begin(), __l.end()); }
-#endif // C++11
-
-#if __cplusplus >= 201703L
- /**
- * @brief Replace range of characters with string_view.
- * @param __pos The position to replace at.
- * @param __n The number of characters to replace.
- * @param __svt The object convertible to string_view to insert.
- * @return Reference to this string.
- */
- template<typename _Tp>
- _If_sv<_Tp, basic_string&>
- replace(size_type __pos, size_type __n, const _Tp& __svt)
- {
- __sv_type __sv = __svt;
- return this->replace(__pos, __n, __sv.data(), __sv.size());
- }
-
- /**
- * @brief Replace range of characters with string_view.
- * @param __pos1 The position to replace at.
- * @param __n1 The number of characters to replace.
- * @param __svt The object convertible to string_view to insert from.
- * @param __pos2 The position in the string_view to insert from.
- * @param __n2 The number of characters to insert.
- * @return Reference to this string.
- */
- template<typename _Tp>
- _If_sv<_Tp, basic_string&>
- replace(size_type __pos1, size_type __n1, const _Tp& __svt,
- size_type __pos2, size_type __n2 = npos)
- {
- __sv_type __sv = __svt;
- return this->replace(__pos1, __n1,
- __sv.data()
- + std::__sv_check(__sv.size(), __pos2, "basic_string::replace"),
- std::__sv_limit(__sv.size(), __pos2, __n2));
- }
-
- /**
- * @brief Replace range of characters with string_view.
- * @param __i1 An iterator referencing the start position
- to replace at.
- * @param __i2 An iterator referencing the end position
- for the replace.
- * @param __svt The object convertible to string_view to insert from.
- * @return Reference to this string.
- */
- template<typename _Tp>
- _If_sv<_Tp, basic_string&>
- replace(const_iterator __i1, const_iterator __i2, const _Tp& __svt)
- {
- __sv_type __sv = __svt;
- return this->replace(__i1 - begin(), __i2 - __i1, __sv);
- }
-#endif // C++17
-
- private:
- template<class _Integer>
- basic_string&
- _M_replace_dispatch(iterator __i1, iterator __i2, _Integer __n,
- _Integer __val, __true_type)
- { return _M_replace_aux(__i1 - _M_ibegin(), __i2 - __i1, __n, __val); }
-
- template<class _InputIterator>
- basic_string&
- _M_replace_dispatch(iterator __i1, iterator __i2, _InputIterator __k1,
- _InputIterator __k2, __false_type);
-
- basic_string&
- _M_replace_aux(size_type __pos1, size_type __n1, size_type __n2,
- _CharT __c);
-
- basic_string&
- _M_replace_safe(size_type __pos1, size_type __n1, const _CharT* __s,
- size_type __n2);
-
- // _S_construct_aux is used to implement the 21.3.1 para 15 which
- // requires special behaviour if _InIter is an integral type
- template<class _InIterator>
- static _CharT*
- _S_construct_aux(_InIterator __beg, _InIterator __end,
- const _Alloc& __a, __false_type)
- {
- typedef typename iterator_traits<_InIterator>::iterator_category _Tag;
- return _S_construct(__beg, __end, __a, _Tag());
- }
-
- // _GLIBCXX_RESOLVE_LIB_DEFECTS
- // 438. Ambiguity in the "do the right thing" clause
- template<class _Integer>
- static _CharT*
- _S_construct_aux(_Integer __beg, _Integer __end,
- const _Alloc& __a, __true_type)
- { return _S_construct_aux_2(static_cast<size_type>(__beg),
- __end, __a); }
-
- static _CharT*
- _S_construct_aux_2(size_type __req, _CharT __c, const _Alloc& __a)
- { return _S_construct(__req, __c, __a); }
-
- template<class _InIterator>
- static _CharT*
- _S_construct(_InIterator __beg, _InIterator __end, const _Alloc& __a)
- {
- typedef typename std::__is_integer<_InIterator>::__type _Integral;
- return _S_construct_aux(__beg, __end, __a, _Integral());
- }
-
- // For Input Iterators, used in istreambuf_iterators, etc.
- template<class _InIterator>
- static _CharT*
- _S_construct(_InIterator __beg, _InIterator __end, const _Alloc& __a,
- input_iterator_tag);
-
- // For forward_iterators up to random_access_iterators, used for
- // string::iterator, _CharT*, etc.
- template<class _FwdIterator>
- static _CharT*
- _S_construct(_FwdIterator __beg, _FwdIterator __end, const _Alloc& __a,
- forward_iterator_tag);
-
- static _CharT*
- _S_construct(size_type __req, _CharT __c, const _Alloc& __a);
-
- public:
-
- /**
- * @brief Copy substring into C string.
- * @param __s C string to copy value into.
- * @param __n Number of characters to copy.
- * @param __pos Index of first character to copy.
- * @return Number of characters actually copied
- * @throw std::out_of_range If __pos > size().
- *
- * Copies up to @a __n characters starting at @a __pos into the
- * C string @a __s. If @a __pos is %greater than size(),
- * out_of_range is thrown.
- */
- size_type
- copy(_CharT* __s, size_type __n, size_type __pos = 0) const;
-
- /**
- * @brief Swap contents with another string.
- * @param __s String to swap with.
- *
- * Exchanges the contents of this string with that of @a __s in constant
- * time.
- */
- void
- swap(basic_string& __s)
- _GLIBCXX_NOEXCEPT_IF(allocator_traits<_Alloc>::is_always_equal::value);
-
- // String operations:
- /**
- * @brief Return const pointer to null-terminated contents.
- *
- * This is a handle to internal data. Do not modify or dire things may
- * happen.
- */
- const _CharT*
- c_str() const _GLIBCXX_NOEXCEPT
- { return _M_data(); }
-
- /**
- * @brief Return const pointer to contents.
- *
- * This is a pointer to internal data. It is undefined to modify
- * the contents through the returned pointer. To get a pointer that
- * allows modifying the contents use @c &str[0] instead,
- * (or in C++17 the non-const @c str.data() overload).
- */
- const _CharT*
- data() const _GLIBCXX_NOEXCEPT
- { return _M_data(); }
-
-#if __cplusplus >= 201703L
- /**
- * @brief Return non-const pointer to contents.
- *
- * This is a pointer to the character sequence held by the string.
- * Modifying the characters in the sequence is allowed.
- */
- _CharT*
- data() noexcept
- {
- _M_leak();
- return _M_data();
- }
-#endif
-
- /**
- * @brief Return copy of allocator used to construct this string.
- */
- allocator_type
- get_allocator() const _GLIBCXX_NOEXCEPT
- { return _M_dataplus; }
-
- /**
- * @brief Find position of a C substring.
- * @param __s C string to locate.
- * @param __pos Index of character to search from.
- * @param __n Number of characters from @a s to search for.
- * @return Index of start of first occurrence.
- *
- * Starting from @a __pos, searches forward for the first @a
- * __n characters in @a __s within this string. If found,
- * returns the index where it begins. If not found, returns
- * npos.
- */
- size_type
- find(const _CharT* __s, size_type __pos, size_type __n) const
- _GLIBCXX_NOEXCEPT;
-
- /**
- * @brief Find position of a string.
- * @param __str String to locate.
- * @param __pos Index of character to search from (default 0).
- * @return Index of start of first occurrence.
- *
- * Starting from @a __pos, searches forward for value of @a __str within
- * this string. If found, returns the index where it begins. If not
- * found, returns npos.
- */
- size_type
- find(const basic_string& __str, size_type __pos = 0) const
- _GLIBCXX_NOEXCEPT
- { return this->find(__str.data(), __pos, __str.size()); }
-
- /**
- * @brief Find position of a C string.
- * @param __s C string to locate.
- * @param __pos Index of character to search from (default 0).
- * @return Index of start of first occurrence.
- *
- * Starting from @a __pos, searches forward for the value of @a
- * __s within this string. If found, returns the index where
- * it begins. If not found, returns npos.
- */
- size_type
- find(const _CharT* __s, size_type __pos = 0) const _GLIBCXX_NOEXCEPT
- {
- __glibcxx_requires_string(__s);
- return this->find(__s, __pos, traits_type::length(__s));
- }
-
- /**
- * @brief Find position of a character.
- * @param __c Character to locate.
- * @param __pos Index of character to search from (default 0).
- * @return Index of first occurrence.
- *
- * Starting from @a __pos, searches forward for @a __c within
- * this string. If found, returns the index where it was
- * found. If not found, returns npos.
- */
- size_type
- find(_CharT __c, size_type __pos = 0) const _GLIBCXX_NOEXCEPT;
-
-#if __cplusplus >= 201703L
- /**
- * @brief Find position of a string_view.
- * @param __svt The object convertible to string_view to locate.
- * @param __pos Index of character to search from (default 0).
- * @return Index of start of first occurrence.
- */
- template<typename _Tp>
- _If_sv<_Tp, size_type>
- find(const _Tp& __svt, size_type __pos = 0) const
- noexcept(is_same<_Tp, __sv_type>::value)
- {
- __sv_type __sv = __svt;
- return this->find(__sv.data(), __pos, __sv.size());
- }
-#endif // C++17
-
- /**
- * @brief Find last position of a string.
- * @param __str String to locate.
- * @param __pos Index of character to search back from (default end).
- * @return Index of start of last occurrence.
- *
- * Starting from @a __pos, searches backward for value of @a
- * __str within this string. If found, returns the index where
- * it begins. If not found, returns npos.
- */
- size_type
- rfind(const basic_string& __str, size_type __pos = npos) const
- _GLIBCXX_NOEXCEPT
- { return this->rfind(__str.data(), __pos, __str.size()); }
-
- /**
- * @brief Find last position of a C substring.
- * @param __s C string to locate.
- * @param __pos Index of character to search back from.
- * @param __n Number of characters from s to search for.
- * @return Index of start of last occurrence.
- *
- * Starting from @a __pos, searches backward for the first @a
- * __n characters in @a __s within this string. If found,
- * returns the index where it begins. If not found, returns
- * npos.
- */
- size_type
- rfind(const _CharT* __s, size_type __pos, size_type __n) const
- _GLIBCXX_NOEXCEPT;
-
- /**
- * @brief Find last position of a C string.
- * @param __s C string to locate.
- * @param __pos Index of character to start search at (default end).
- * @return Index of start of last occurrence.
- *
- * Starting from @a __pos, searches backward for the value of
- * @a __s within this string. If found, returns the index
- * where it begins. If not found, returns npos.
- */
- size_type
- rfind(const _CharT* __s, size_type __pos = npos) const _GLIBCXX_NOEXCEPT
- {
- __glibcxx_requires_string(__s);
- return this->rfind(__s, __pos, traits_type::length(__s));
- }
-
- /**
- * @brief Find last position of a character.
- * @param __c Character to locate.
- * @param __pos Index of character to search back from (default end).
- * @return Index of last occurrence.
- *
- * Starting from @a __pos, searches backward for @a __c within
- * this string. If found, returns the index where it was
- * found. If not found, returns npos.
- */
- size_type
- rfind(_CharT __c, size_type __pos = npos) const _GLIBCXX_NOEXCEPT;
-
-#if __cplusplus >= 201703L
- /**
- * @brief Find last position of a string_view.
- * @param __svt The object convertible to string_view to locate.
- * @param __pos Index of character to search back from (default end).
- * @return Index of start of last occurrence.
- */
- template<typename _Tp>
- _If_sv<_Tp, size_type>
- rfind(const _Tp& __svt, size_type __pos = npos) const
- noexcept(is_same<_Tp, __sv_type>::value)
- {
- __sv_type __sv = __svt;
- return this->rfind(__sv.data(), __pos, __sv.size());
- }
-#endif // C++17
-
- /**
- * @brief Find position of a character of string.
- * @param __str String containing characters to locate.
- * @param __pos Index of character to search from (default 0).
- * @return Index of first occurrence.
- *
- * Starting from @a __pos, searches forward for one of the
- * characters of @a __str within this string. If found,
- * returns the index where it was found. If not found, returns
- * npos.
- */
- size_type
- find_first_of(const basic_string& __str, size_type __pos = 0) const
- _GLIBCXX_NOEXCEPT
- { return this->find_first_of(__str.data(), __pos, __str.size()); }
-
- /**
- * @brief Find position of a character of C substring.
- * @param __s String containing characters to locate.
- * @param __pos Index of character to search from.
- * @param __n Number of characters from s to search for.
- * @return Index of first occurrence.
- *
- * Starting from @a __pos, searches forward for one of the
- * first @a __n characters of @a __s within this string. If
- * found, returns the index where it was found. If not found,
- * returns npos.
- */
- size_type
- find_first_of(const _CharT* __s, size_type __pos, size_type __n) const
- _GLIBCXX_NOEXCEPT;
-
- /**
- * @brief Find position of a character of C string.
- * @param __s String containing characters to locate.
- * @param __pos Index of character to search from (default 0).
- * @return Index of first occurrence.
- *
- * Starting from @a __pos, searches forward for one of the
- * characters of @a __s within this string. If found, returns
- * the index where it was found. If not found, returns npos.
- */
- size_type
- find_first_of(const _CharT* __s, size_type __pos = 0) const
- _GLIBCXX_NOEXCEPT
- {
- __glibcxx_requires_string(__s);
- return this->find_first_of(__s, __pos, traits_type::length(__s));
- }
-
- /**
- * @brief Find position of a character.
- * @param __c Character to locate.
- * @param __pos Index of character to search from (default 0).
- * @return Index of first occurrence.
- *
- * Starting from @a __pos, searches forward for the character
- * @a __c within this string. If found, returns the index
- * where it was found. If not found, returns npos.
- *
- * Note: equivalent to find(__c, __pos).
- */
- size_type
- find_first_of(_CharT __c, size_type __pos = 0) const _GLIBCXX_NOEXCEPT
- { return this->find(__c, __pos); }
-
-#if __cplusplus >= 201703L
- /**
- * @brief Find position of a character of a string_view.
- * @param __svt An object convertible to string_view containing
- * characters to locate.
- * @param __pos Index of character to search from (default 0).
- * @return Index of first occurrence.
- */
- template<typename _Tp>
- _If_sv<_Tp, size_type>
- find_first_of(const _Tp& __svt, size_type __pos = 0) const
- noexcept(is_same<_Tp, __sv_type>::value)
- {
- __sv_type __sv = __svt;
- return this->find_first_of(__sv.data(), __pos, __sv.size());
- }
-#endif // C++17
-
- /**
- * @brief Find last position of a character of string.
- * @param __str String containing characters to locate.
- * @param __pos Index of character to search back from (default end).
- * @return Index of last occurrence.
- *
- * Starting from @a __pos, searches backward for one of the
- * characters of @a __str within this string. If found,
- * returns the index where it was found. If not found, returns
- * npos.
- */
- size_type
- find_last_of(const basic_string& __str, size_type __pos = npos) const
- _GLIBCXX_NOEXCEPT
- { return this->find_last_of(__str.data(), __pos, __str.size()); }
-
- /**
- * @brief Find last position of a character of C substring.
- * @param __s C string containing characters to locate.
- * @param __pos Index of character to search back from.
- * @param __n Number of characters from s to search for.
- * @return Index of last occurrence.
- *
- * Starting from @a __pos, searches backward for one of the
- * first @a __n characters of @a __s within this string. If
- * found, returns the index where it was found. If not found,
- * returns npos.
- */
- size_type
- find_last_of(const _CharT* __s, size_type __pos, size_type __n) const
- _GLIBCXX_NOEXCEPT;
-
- /**
- * @brief Find last position of a character of C string.
- * @param __s C string containing characters to locate.
- * @param __pos Index of character to search back from (default end).
- * @return Index of last occurrence.
- *
- * Starting from @a __pos, searches backward for one of the
- * characters of @a __s within this string. If found, returns
- * the index where it was found. If not found, returns npos.
- */
- size_type
- find_last_of(const _CharT* __s, size_type __pos = npos) const
- _GLIBCXX_NOEXCEPT
- {
- __glibcxx_requires_string(__s);
- return this->find_last_of(__s, __pos, traits_type::length(__s));
- }
-
- /**
- * @brief Find last position of a character.
- * @param __c Character to locate.
- * @param __pos Index of character to search back from (default end).
- * @return Index of last occurrence.
- *
- * Starting from @a __pos, searches backward for @a __c within
- * this string. If found, returns the index where it was
- * found. If not found, returns npos.
- *
- * Note: equivalent to rfind(__c, __pos).
- */
- size_type
- find_last_of(_CharT __c, size_type __pos = npos) const _GLIBCXX_NOEXCEPT
- { return this->rfind(__c, __pos); }
-
-#if __cplusplus >= 201703L
- /**
- * @brief Find last position of a character of string.
- * @param __svt An object convertible to string_view containing
- * characters to locate.
- * @param __pos Index of character to search back from (default end).
- * @return Index of last occurrence.
- */
- template<typename _Tp>
- _If_sv<_Tp, size_type>
- find_last_of(const _Tp& __svt, size_type __pos = npos) const
- noexcept(is_same<_Tp, __sv_type>::value)
- {
- __sv_type __sv = __svt;
- return this->find_last_of(__sv.data(), __pos, __sv.size());
- }
-#endif // C++17
-
- /**
- * @brief Find position of a character not in string.
- * @param __str String containing characters to avoid.
- * @param __pos Index of character to search from (default 0).
- * @return Index of first occurrence.
- *
- * Starting from @a __pos, searches forward for a character not contained
- * in @a __str within this string. If found, returns the index where it
- * was found. If not found, returns npos.
- */
- size_type
- find_first_not_of(const basic_string& __str, size_type __pos = 0) const
- _GLIBCXX_NOEXCEPT
- { return this->find_first_not_of(__str.data(), __pos, __str.size()); }
-
- /**
- * @brief Find position of a character not in C substring.
- * @param __s C string containing characters to avoid.
- * @param __pos Index of character to search from.
- * @param __n Number of characters from __s to consider.
- * @return Index of first occurrence.
- *
- * Starting from @a __pos, searches forward for a character not
- * contained in the first @a __n characters of @a __s within
- * this string. If found, returns the index where it was
- * found. If not found, returns npos.
- */
- size_type
- find_first_not_of(const _CharT* __s, size_type __pos,
- size_type __n) const _GLIBCXX_NOEXCEPT;
-
- /**
- * @brief Find position of a character not in C string.
- * @param __s C string containing characters to avoid.
- * @param __pos Index of character to search from (default 0).
- * @return Index of first occurrence.
- *
- * Starting from @a __pos, searches forward for a character not
- * contained in @a __s within this string. If found, returns
- * the index where it was found. If not found, returns npos.
- */
- size_type
- find_first_not_of(const _CharT* __s, size_type __pos = 0) const
- _GLIBCXX_NOEXCEPT
- {
- __glibcxx_requires_string(__s);
- return this->find_first_not_of(__s, __pos, traits_type::length(__s));
- }
-
- /**
- * @brief Find position of a different character.
- * @param __c Character to avoid.
- * @param __pos Index of character to search from (default 0).
- * @return Index of first occurrence.
- *
- * Starting from @a __pos, searches forward for a character
- * other than @a __c within this string. If found, returns the
- * index where it was found. If not found, returns npos.
- */
- size_type
- find_first_not_of(_CharT __c, size_type __pos = 0) const
- _GLIBCXX_NOEXCEPT;
-
-#if __cplusplus >= 201703L
- /**
- * @brief Find position of a character not in a string_view.
- * @param __svt An object convertible to string_view containing
- * characters to avoid.
- * @param __pos Index of character to search from (default 0).
- * @return Index of first occurrence.
- */
- template<typename _Tp>
- _If_sv<_Tp, size_type>
- find_first_not_of(const _Tp& __svt, size_type __pos = 0) const
- noexcept(is_same<_Tp, __sv_type>::value)
- {
- __sv_type __sv = __svt;
- return this->find_first_not_of(__sv.data(), __pos, __sv.size());
- }
-#endif // C++17
-
- /**
- * @brief Find last position of a character not in string.
- * @param __str String containing characters to avoid.
- * @param __pos Index of character to search back from (default end).
- * @return Index of last occurrence.
- *
- * Starting from @a __pos, searches backward for a character
- * not contained in @a __str within this string. If found,
- * returns the index where it was found. If not found, returns
- * npos.
- */
- size_type
- find_last_not_of(const basic_string& __str, size_type __pos = npos) const
- _GLIBCXX_NOEXCEPT
- { return this->find_last_not_of(__str.data(), __pos, __str.size()); }
-
- /**
- * @brief Find last position of a character not in C substring.
- * @param __s C string containing characters to avoid.
- * @param __pos Index of character to search back from.
- * @param __n Number of characters from s to consider.
- * @return Index of last occurrence.
- *
- * Starting from @a __pos, searches backward for a character not
- * contained in the first @a __n characters of @a __s within this string.
- * If found, returns the index where it was found. If not found,
- * returns npos.
- */
- size_type
- find_last_not_of(const _CharT* __s, size_type __pos,
- size_type __n) const _GLIBCXX_NOEXCEPT;
- /**
- * @brief Find last position of a character not in C string.
- * @param __s C string containing characters to avoid.
- * @param __pos Index of character to search back from (default end).
- * @return Index of last occurrence.
- *
- * Starting from @a __pos, searches backward for a character
- * not contained in @a __s within this string. If found,
- * returns the index where it was found. If not found, returns
- * npos.
- */
- size_type
- find_last_not_of(const _CharT* __s, size_type __pos = npos) const
- _GLIBCXX_NOEXCEPT
- {
- __glibcxx_requires_string(__s);
- return this->find_last_not_of(__s, __pos, traits_type::length(__s));
- }
-
- /**
- * @brief Find last position of a different character.
- * @param __c Character to avoid.
- * @param __pos Index of character to search back from (default end).
- * @return Index of last occurrence.
- *
- * Starting from @a __pos, searches backward for a character other than
- * @a __c within this string. If found, returns the index where it was
- * found. If not found, returns npos.
- */
- size_type
- find_last_not_of(_CharT __c, size_type __pos = npos) const
- _GLIBCXX_NOEXCEPT;
-
-#if __cplusplus >= 201703L
- /**
- * @brief Find last position of a character not in a string_view.
- * @param __svt An object convertible to string_view containing
- * characters to avoid.
- * @param __pos Index of character to search back from (default end).
- * @return Index of last occurrence.
- */
- template<typename _Tp>
- _If_sv<_Tp, size_type>
- find_last_not_of(const _Tp& __svt, size_type __pos = npos) const
- noexcept(is_same<_Tp, __sv_type>::value)
- {
- __sv_type __sv = __svt;
- return this->find_last_not_of(__sv.data(), __pos, __sv.size());
- }
-#endif // C++17
-
- /**
- * @brief Get a substring.
- * @param __pos Index of first character (default 0).
- * @param __n Number of characters in substring (default remainder).
- * @return The new string.
- * @throw std::out_of_range If __pos > size().
- *
- * Construct and return a new string using the @a __n
- * characters starting at @a __pos. If the string is too
- * short, use the remainder of the characters. If @a __pos is
- * beyond the end of the string, out_of_range is thrown.
- */
- basic_string
- substr(size_type __pos = 0, size_type __n = npos) const
- { return basic_string(*this,
- _M_check(__pos, "basic_string::substr"), __n); }
-
- /**
- * @brief Compare to a string.
- * @param __str String to compare against.
- * @return Integer < 0, 0, or > 0.
- *
- * Returns an integer < 0 if this string is ordered before @a
- * __str, 0 if their values are equivalent, or > 0 if this
- * string is ordered after @a __str. Determines the effective
- * length rlen of the strings to compare as the smallest of
- * size() and str.size(). The function then compares the two
- * strings by calling traits::compare(data(), str.data(),rlen).
- * If the result of the comparison is nonzero returns it,
- * otherwise the shorter one is ordered first.
- */
- int
- compare(const basic_string& __str) const
- {
- const size_type __size = this->size();
- const size_type __osize = __str.size();
- const size_type __len = std::min(__size, __osize);
-
- int __r = traits_type::compare(_M_data(), __str.data(), __len);
- if (!__r)
- __r = _S_compare(__size, __osize);
- return __r;
- }
-
-#if __cplusplus >= 201703L
- /**
- * @brief Compare to a string_view.
- * @param __svt An object convertible to string_view to compare against.
- * @return Integer < 0, 0, or > 0.
- */
- template<typename _Tp>
- _If_sv<_Tp, int>
- compare(const _Tp& __svt) const
- noexcept(is_same<_Tp, __sv_type>::value)
- {
- __sv_type __sv = __svt;
- const size_type __size = this->size();
- const size_type __osize = __sv.size();
- const size_type __len = std::min(__size, __osize);
-
- int __r = traits_type::compare(_M_data(), __sv.data(), __len);
- if (!__r)
- __r = _S_compare(__size, __osize);
- return __r;
- }
-
- /**
- * @brief Compare to a string_view.
- * @param __pos A position in the string to start comparing from.
- * @param __n The number of characters to compare.
- * @param __svt An object convertible to string_view to compare
- * against.
- * @return Integer < 0, 0, or > 0.
- */
- template<typename _Tp>
- _If_sv<_Tp, int>
- compare(size_type __pos, size_type __n, const _Tp& __svt) const
- noexcept(is_same<_Tp, __sv_type>::value)
- {
- __sv_type __sv = __svt;
- return __sv_type(*this).substr(__pos, __n).compare(__sv);
- }
-
- /**
- * @brief Compare to a string_view.
- * @param __pos1 A position in the string to start comparing from.
- * @param __n1 The number of characters to compare.
- * @param __svt An object convertible to string_view to compare
- * against.
- * @param __pos2 A position in the string_view to start comparing from.
- * @param __n2 The number of characters to compare.
- * @return Integer < 0, 0, or > 0.
- */
- template<typename _Tp>
- _If_sv<_Tp, int>
- compare(size_type __pos1, size_type __n1, const _Tp& __svt,
- size_type __pos2, size_type __n2 = npos) const
- noexcept(is_same<_Tp, __sv_type>::value)
- {
- __sv_type __sv = __svt;
- return __sv_type(*this)
- .substr(__pos1, __n1).compare(__sv.substr(__pos2, __n2));
- }
-#endif // C++17
-
- /**
- * @brief Compare substring to a string.
- * @param __pos Index of first character of substring.
- * @param __n Number of characters in substring.
- * @param __str String to compare against.
- * @return Integer < 0, 0, or > 0.
- *
- * Form the substring of this string from the @a __n characters
- * starting at @a __pos. Returns an integer < 0 if the
- * substring is ordered before @a __str, 0 if their values are
- * equivalent, or > 0 if the substring is ordered after @a
- * __str. Determines the effective length rlen of the strings
- * to compare as the smallest of the length of the substring
- * and @a __str.size(). The function then compares the two
- * strings by calling
- * traits::compare(substring.data(),str.data(),rlen). If the
- * result of the comparison is nonzero returns it, otherwise
- * the shorter one is ordered first.
- */
- int
- compare(size_type __pos, size_type __n, const basic_string& __str) const;
-
- /**
- * @brief Compare substring to a substring.
- * @param __pos1 Index of first character of substring.
- * @param __n1 Number of characters in substring.
- * @param __str String to compare against.
- * @param __pos2 Index of first character of substring of str.
- * @param __n2 Number of characters in substring of str.
- * @return Integer < 0, 0, or > 0.
- *
- * Form the substring of this string from the @a __n1
- * characters starting at @a __pos1. Form the substring of @a
- * __str from the @a __n2 characters starting at @a __pos2.
- * Returns an integer < 0 if this substring is ordered before
- * the substring of @a __str, 0 if their values are equivalent,
- * or > 0 if this substring is ordered after the substring of
- * @a __str. Determines the effective length rlen of the
- * strings to compare as the smallest of the lengths of the
- * substrings. The function then compares the two strings by
- * calling
- * traits::compare(substring.data(),str.substr(pos2,n2).data(),rlen).
- * If the result of the comparison is nonzero returns it,
- * otherwise the shorter one is ordered first.
- */
- int
- compare(size_type __pos1, size_type __n1, const basic_string& __str,
- size_type __pos2, size_type __n2 = npos) const;
-
- /**
- * @brief Compare to a C string.
- * @param __s C string to compare against.
- * @return Integer < 0, 0, or > 0.
- *
- * Returns an integer < 0 if this string is ordered before @a __s, 0 if
- * their values are equivalent, or > 0 if this string is ordered after
- * @a __s. Determines the effective length rlen of the strings to
- * compare as the smallest of size() and the length of a string
- * constructed from @a __s. The function then compares the two strings
- * by calling traits::compare(data(),s,rlen). If the result of the
- * comparison is nonzero returns it, otherwise the shorter one is
- * ordered first.
- */
- int
- compare(const _CharT* __s) const _GLIBCXX_NOEXCEPT;
-
- // _GLIBCXX_RESOLVE_LIB_DEFECTS
- // 5 String::compare specification questionable
- /**
- * @brief Compare substring to a C string.
- * @param __pos Index of first character of substring.
- * @param __n1 Number of characters in substring.
- * @param __s C string to compare against.
- * @return Integer < 0, 0, or > 0.
- *
- * Form the substring of this string from the @a __n1
- * characters starting at @a pos. Returns an integer < 0 if
- * the substring is ordered before @a __s, 0 if their values
- * are equivalent, or > 0 if the substring is ordered after @a
- * __s. Determines the effective length rlen of the strings to
- * compare as the smallest of the length of the substring and
- * the length of a string constructed from @a __s. The
- * function then compares the two string by calling
- * traits::compare(substring.data(),__s,rlen). If the result of
- * the comparison is nonzero returns it, otherwise the shorter
- * one is ordered first.
- */
- int
- compare(size_type __pos, size_type __n1, const _CharT* __s) const;
-
- /**
- * @brief Compare substring against a character %array.
- * @param __pos Index of first character of substring.
- * @param __n1 Number of characters in substring.
- * @param __s character %array to compare against.
- * @param __n2 Number of characters of s.
- * @return Integer < 0, 0, or > 0.
- *
- * Form the substring of this string from the @a __n1
- * characters starting at @a __pos. Form a string from the
- * first @a __n2 characters of @a __s. Returns an integer < 0
- * if this substring is ordered before the string from @a __s,
- * 0 if their values are equivalent, or > 0 if this substring
- * is ordered after the string from @a __s. Determines the
- * effective length rlen of the strings to compare as the
- * smallest of the length of the substring and @a __n2. The
- * function then compares the two strings by calling
- * traits::compare(substring.data(),s,rlen). If the result of
- * the comparison is nonzero returns it, otherwise the shorter
- * one is ordered first.
- *
- * NB: s must have at least n2 characters, '\\0' has
- * no special meaning.
- */
- int
- compare(size_type __pos, size_type __n1, const _CharT* __s,
- size_type __n2) const;
-
-#if __cplusplus > 201703L
- bool
- starts_with(basic_string_view<_CharT, _Traits> __x) const noexcept
- { return __sv_type(this->data(), this->size()).starts_with(__x); }
-
- bool
- starts_with(_CharT __x) const noexcept
- { return __sv_type(this->data(), this->size()).starts_with(__x); }
-
- bool
- starts_with(const _CharT* __x) const noexcept
- { return __sv_type(this->data(), this->size()).starts_with(__x); }
-
- bool
- ends_with(basic_string_view<_CharT, _Traits> __x) const noexcept
- { return __sv_type(this->data(), this->size()).ends_with(__x); }
-
- bool
- ends_with(_CharT __x) const noexcept
- { return __sv_type(this->data(), this->size()).ends_with(__x); }
-
- bool
- ends_with(const _CharT* __x) const noexcept
- { return __sv_type(this->data(), this->size()).ends_with(__x); }
-#endif // C++20
-
-#if __cplusplus >= 202011L \
- || (__cplusplus == 202002L && !defined __STRICT_ANSI__)
- bool
- contains(basic_string_view<_CharT, _Traits> __x) const noexcept
- { return __sv_type(this->data(), this->size()).contains(__x); }
-
- bool
- contains(_CharT __x) const noexcept
- { return __sv_type(this->data(), this->size()).contains(__x); }
-
- bool
- contains(const _CharT* __x) const noexcept
- { return __sv_type(this->data(), this->size()).contains(__x); }
-#endif // C++23
-
-# ifdef _GLIBCXX_TM_TS_INTERNAL
- friend void
- ::_txnal_cow_string_C1_for_exceptions(void* that, const char* s,
- void* exc);
- friend const char*
- ::_txnal_cow_string_c_str(const void *that);
- friend void
- ::_txnal_cow_string_D1(void *that);
- friend void
- ::_txnal_cow_string_D1_commit(void *that);
-# endif
- };
-#endif // !_GLIBCXX_USE_CXX11_ABI
+namespace std _GLIBCXX_VISIBILITY(default)
+{
+_GLIBCXX_BEGIN_NAMESPACE_VERSION
#if __cpp_deduction_guides >= 201606
_GLIBCXX_BEGIN_NAMESPACE_CXX11
return __n;
}
-#else // !_GLIBCXX_USE_CXX11_ABI
-
- template<typename _CharT, typename _Traits, typename _Alloc>
- const typename basic_string<_CharT, _Traits, _Alloc>::size_type
- basic_string<_CharT, _Traits, _Alloc>::
- _Rep::_S_max_size = (((npos - sizeof(_Rep_base))/sizeof(_CharT)) - 1) / 4;
-
- template<typename _CharT, typename _Traits, typename _Alloc>
- const _CharT
- basic_string<_CharT, _Traits, _Alloc>::
- _Rep::_S_terminal = _CharT();
-
- template<typename _CharT, typename _Traits, typename _Alloc>
- const typename basic_string<_CharT, _Traits, _Alloc>::size_type
- basic_string<_CharT, _Traits, _Alloc>::npos;
-
- // Linker sets _S_empty_rep_storage to all 0s (one reference, empty string)
- // at static init time (before static ctors are run).
- template<typename _CharT, typename _Traits, typename _Alloc>
- typename basic_string<_CharT, _Traits, _Alloc>::size_type
- basic_string<_CharT, _Traits, _Alloc>::_Rep::_S_empty_rep_storage[
- (sizeof(_Rep_base) + sizeof(_CharT) + sizeof(size_type) - 1) /
- sizeof(size_type)];
-
- // NB: This is the special case for Input Iterators, used in
- // istreambuf_iterators, etc.
- // Input Iterators have a cost structure very different from
- // pointers, calling for a different coding style.
- template<typename _CharT, typename _Traits, typename _Alloc>
- template<typename _InIterator>
- _CharT*
- basic_string<_CharT, _Traits, _Alloc>::
- _S_construct(_InIterator __beg, _InIterator __end, const _Alloc& __a,
- input_iterator_tag)
- {
-#if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
- if (__beg == __end && __a == _Alloc())
- return _S_empty_rep()._M_refdata();
-#endif
- // Avoid reallocation for common case.
- _CharT __buf[128];
- size_type __len = 0;
- while (__beg != __end && __len < sizeof(__buf) / sizeof(_CharT))
- {
- __buf[__len++] = *__beg;
- ++__beg;
- }
- _Rep* __r = _Rep::_S_create(__len, size_type(0), __a);
- _M_copy(__r->_M_refdata(), __buf, __len);
- __try
- {
- while (__beg != __end)
- {
- if (__len == __r->_M_capacity)
- {
- // Allocate more space.
- _Rep* __another = _Rep::_S_create(__len + 1, __len, __a);
- _M_copy(__another->_M_refdata(), __r->_M_refdata(), __len);
- __r->_M_destroy(__a);
- __r = __another;
- }
- __r->_M_refdata()[__len++] = *__beg;
- ++__beg;
- }
- }
- __catch(...)
- {
- __r->_M_destroy(__a);
- __throw_exception_again;
- }
- __r->_M_set_length_and_sharable(__len);
- return __r->_M_refdata();
- }
-
- template<typename _CharT, typename _Traits, typename _Alloc>
- template <typename _InIterator>
- _CharT*
- basic_string<_CharT, _Traits, _Alloc>::
- _S_construct(_InIterator __beg, _InIterator __end, const _Alloc& __a,
- forward_iterator_tag)
- {
-#if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
- if (__beg == __end && __a == _Alloc())
- return _S_empty_rep()._M_refdata();
-#endif
- // NB: Not required, but considered best practice.
- if (__gnu_cxx::__is_null_pointer(__beg) && __beg != __end)
- __throw_logic_error(__N("basic_string::_S_construct null not valid"));
-
- const size_type __dnew = static_cast<size_type>(std::distance(__beg,
- __end));
- // Check for out_of_range and length_error exceptions.
- _Rep* __r = _Rep::_S_create(__dnew, size_type(0), __a);
- __try
- { _S_copy_chars(__r->_M_refdata(), __beg, __end); }
- __catch(...)
- {
- __r->_M_destroy(__a);
- __throw_exception_again;
- }
- __r->_M_set_length_and_sharable(__dnew);
- return __r->_M_refdata();
- }
-
- template<typename _CharT, typename _Traits, typename _Alloc>
- _CharT*
- basic_string<_CharT, _Traits, _Alloc>::
- _S_construct(size_type __n, _CharT __c, const _Alloc& __a)
- {
-#if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
- if (__n == 0 && __a == _Alloc())
- return _S_empty_rep()._M_refdata();
-#endif
- // Check for out_of_range and length_error exceptions.
- _Rep* __r = _Rep::_S_create(__n, size_type(0), __a);
- if (__n)
- _M_assign(__r->_M_refdata(), __n, __c);
-
- __r->_M_set_length_and_sharable(__n);
- return __r->_M_refdata();
- }
-
- template<typename _CharT, typename _Traits, typename _Alloc>
- basic_string<_CharT, _Traits, _Alloc>::
- basic_string(const basic_string& __str, size_type __pos, const _Alloc& __a)
- : _M_dataplus(_S_construct(__str._M_data()
- + __str._M_check(__pos,
- "basic_string::basic_string"),
- __str._M_data() + __str._M_limit(__pos, npos)
- + __pos, __a), __a)
- { }
-
- template<typename _CharT, typename _Traits, typename _Alloc>
- basic_string<_CharT, _Traits, _Alloc>::
- basic_string(const basic_string& __str, size_type __pos, size_type __n)
- : _M_dataplus(_S_construct(__str._M_data()
- + __str._M_check(__pos,
- "basic_string::basic_string"),
- __str._M_data() + __str._M_limit(__pos, __n)
- + __pos, _Alloc()), _Alloc())
- { }
-
- template<typename _CharT, typename _Traits, typename _Alloc>
- basic_string<_CharT, _Traits, _Alloc>::
- basic_string(const basic_string& __str, size_type __pos,
- size_type __n, const _Alloc& __a)
- : _M_dataplus(_S_construct(__str._M_data()
- + __str._M_check(__pos,
- "basic_string::basic_string"),
- __str._M_data() + __str._M_limit(__pos, __n)
- + __pos, __a), __a)
- { }
-
- template<typename _CharT, typename _Traits, typename _Alloc>
- basic_string<_CharT, _Traits, _Alloc>&
- basic_string<_CharT, _Traits, _Alloc>::
- assign(const basic_string& __str)
- {
- if (_M_rep() != __str._M_rep())
- {
- // XXX MT
- const allocator_type __a = this->get_allocator();
- _CharT* __tmp = __str._M_rep()->_M_grab(__a, __str.get_allocator());
- _M_rep()->_M_dispose(__a);
- _M_data(__tmp);
- }
- return *this;
- }
-
- template<typename _CharT, typename _Traits, typename _Alloc>
- basic_string<_CharT, _Traits, _Alloc>&
- basic_string<_CharT, _Traits, _Alloc>::
- assign(const _CharT* __s, size_type __n)
- {
- __glibcxx_requires_string_len(__s, __n);
- _M_check_length(this->size(), __n, "basic_string::assign");
- if (_M_disjunct(__s) || _M_rep()->_M_is_shared())
- return _M_replace_safe(size_type(0), this->size(), __s, __n);
- else
- {
- // Work in-place.
- const size_type __pos = __s - _M_data();
- if (__pos >= __n)
- _M_copy(_M_data(), __s, __n);
- else if (__pos)
- _M_move(_M_data(), __s, __n);
- _M_rep()->_M_set_length_and_sharable(__n);
- return *this;
- }
- }
-
- template<typename _CharT, typename _Traits, typename _Alloc>
- basic_string<_CharT, _Traits, _Alloc>&
- basic_string<_CharT, _Traits, _Alloc>::
- append(size_type __n, _CharT __c)
- {
- if (__n)
- {
- _M_check_length(size_type(0), __n, "basic_string::append");
- const size_type __len = __n + this->size();
- if (__len > this->capacity() || _M_rep()->_M_is_shared())
- this->reserve(__len);
- _M_assign(_M_data() + this->size(), __n, __c);
- _M_rep()->_M_set_length_and_sharable(__len);
- }
- return *this;
- }
-
- template<typename _CharT, typename _Traits, typename _Alloc>
- basic_string<_CharT, _Traits, _Alloc>&
- basic_string<_CharT, _Traits, _Alloc>::
- append(const _CharT* __s, size_type __n)
- {
- __glibcxx_requires_string_len(__s, __n);
- if (__n)
- {
- _M_check_length(size_type(0), __n, "basic_string::append");
- const size_type __len = __n + this->size();
- if (__len > this->capacity() || _M_rep()->_M_is_shared())
- {
- if (_M_disjunct(__s))
- this->reserve(__len);
- else
- {
- const size_type __off = __s - _M_data();
- this->reserve(__len);
- __s = _M_data() + __off;
- }
- }
- _M_copy(_M_data() + this->size(), __s, __n);
- _M_rep()->_M_set_length_and_sharable(__len);
- }
- return *this;
- }
-
- template<typename _CharT, typename _Traits, typename _Alloc>
- basic_string<_CharT, _Traits, _Alloc>&
- basic_string<_CharT, _Traits, _Alloc>::
- append(const basic_string& __str)
- {
- const size_type __size = __str.size();
- if (__size)
- {
- const size_type __len = __size + this->size();
- if (__len > this->capacity() || _M_rep()->_M_is_shared())
- this->reserve(__len);
- _M_copy(_M_data() + this->size(), __str._M_data(), __size);
- _M_rep()->_M_set_length_and_sharable(__len);
- }
- return *this;
- }
-
- template<typename _CharT, typename _Traits, typename _Alloc>
- basic_string<_CharT, _Traits, _Alloc>&
- basic_string<_CharT, _Traits, _Alloc>::
- append(const basic_string& __str, size_type __pos, size_type __n)
- {
- __str._M_check(__pos, "basic_string::append");
- __n = __str._M_limit(__pos, __n);
- if (__n)
- {
- const size_type __len = __n + this->size();
- if (__len > this->capacity() || _M_rep()->_M_is_shared())
- this->reserve(__len);
- _M_copy(_M_data() + this->size(), __str._M_data() + __pos, __n);
- _M_rep()->_M_set_length_and_sharable(__len);
- }
- return *this;
- }
-
- template<typename _CharT, typename _Traits, typename _Alloc>
- basic_string<_CharT, _Traits, _Alloc>&
- basic_string<_CharT, _Traits, _Alloc>::
- insert(size_type __pos, const _CharT* __s, size_type __n)
- {
- __glibcxx_requires_string_len(__s, __n);
- _M_check(__pos, "basic_string::insert");
- _M_check_length(size_type(0), __n, "basic_string::insert");
- if (_M_disjunct(__s) || _M_rep()->_M_is_shared())
- return _M_replace_safe(__pos, size_type(0), __s, __n);
- else
- {
- // Work in-place.
- const size_type __off = __s - _M_data();
- _M_mutate(__pos, 0, __n);
- __s = _M_data() + __off;
- _CharT* __p = _M_data() + __pos;
- if (__s + __n <= __p)
- _M_copy(__p, __s, __n);
- else if (__s >= __p)
- _M_copy(__p, __s + __n, __n);
- else
- {
- const size_type __nleft = __p - __s;
- _M_copy(__p, __s, __nleft);
- _M_copy(__p + __nleft, __p + __n, __n - __nleft);
- }
- return *this;
- }
- }
-
- template<typename _CharT, typename _Traits, typename _Alloc>
- typename basic_string<_CharT, _Traits, _Alloc>::iterator
- basic_string<_CharT, _Traits, _Alloc>::
- erase(iterator __first, iterator __last)
- {
- _GLIBCXX_DEBUG_PEDASSERT(__first >= _M_ibegin() && __first <= __last
- && __last <= _M_iend());
-
- // NB: This isn't just an optimization (bail out early when
- // there is nothing to do, really), it's also a correctness
- // issue vs MT, see libstdc++/40518.
- const size_type __size = __last - __first;
- if (__size)
- {
- const size_type __pos = __first - _M_ibegin();
- _M_mutate(__pos, __size, size_type(0));
- _M_rep()->_M_set_leaked();
- return iterator(_M_data() + __pos);
- }
- else
- return __first;
- }
-
- template<typename _CharT, typename _Traits, typename _Alloc>
- basic_string<_CharT, _Traits, _Alloc>&
- basic_string<_CharT, _Traits, _Alloc>::
- replace(size_type __pos, size_type __n1, const _CharT* __s,
- size_type __n2)
- {
- __glibcxx_requires_string_len(__s, __n2);
- _M_check(__pos, "basic_string::replace");
- __n1 = _M_limit(__pos, __n1);
- _M_check_length(__n1, __n2, "basic_string::replace");
- bool __left;
- if (_M_disjunct(__s) || _M_rep()->_M_is_shared())
- return _M_replace_safe(__pos, __n1, __s, __n2);
- else if ((__left = __s + __n2 <= _M_data() + __pos)
- || _M_data() + __pos + __n1 <= __s)
- {
- // Work in-place: non-overlapping case.
- size_type __off = __s - _M_data();
- __left ? __off : (__off += __n2 - __n1);
- _M_mutate(__pos, __n1, __n2);
- _M_copy(_M_data() + __pos, _M_data() + __off, __n2);
- return *this;
- }
- else
- {
- // Todo: overlapping case.
- const basic_string __tmp(__s, __n2);
- return _M_replace_safe(__pos, __n1, __tmp._M_data(), __n2);
- }
- }
-
- template<typename _CharT, typename _Traits, typename _Alloc>
- void
- basic_string<_CharT, _Traits, _Alloc>::_Rep::
- _M_destroy(const _Alloc& __a) throw ()
- {
- const size_type __size = sizeof(_Rep_base) +
- (this->_M_capacity + 1) * sizeof(_CharT);
- _Raw_bytes_alloc(__a).deallocate(reinterpret_cast<char*>(this), __size);
- }
-
- template<typename _CharT, typename _Traits, typename _Alloc>
- void
- basic_string<_CharT, _Traits, _Alloc>::
- _M_leak_hard()
- {
-#if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
- if (_M_rep() == &_S_empty_rep())
- return;
-#endif
- if (_M_rep()->_M_is_shared())
- _M_mutate(0, 0, 0);
- _M_rep()->_M_set_leaked();
- }
-
- template<typename _CharT, typename _Traits, typename _Alloc>
- void
- basic_string<_CharT, _Traits, _Alloc>::
- _M_mutate(size_type __pos, size_type __len1, size_type __len2)
- {
- const size_type __old_size = this->size();
- const size_type __new_size = __old_size + __len2 - __len1;
- const size_type __how_much = __old_size - __pos - __len1;
-
- if (__new_size > this->capacity() || _M_rep()->_M_is_shared())
- {
- // Must reallocate.
- const allocator_type __a = get_allocator();
- _Rep* __r = _Rep::_S_create(__new_size, this->capacity(), __a);
-
- if (__pos)
- _M_copy(__r->_M_refdata(), _M_data(), __pos);
- if (__how_much)
- _M_copy(__r->_M_refdata() + __pos + __len2,
- _M_data() + __pos + __len1, __how_much);
-
- _M_rep()->_M_dispose(__a);
- _M_data(__r->_M_refdata());
- }
- else if (__how_much && __len1 != __len2)
- {
- // Work in-place.
- _M_move(_M_data() + __pos + __len2,
- _M_data() + __pos + __len1, __how_much);
- }
- _M_rep()->_M_set_length_and_sharable(__new_size);
- }
-
- template<typename _CharT, typename _Traits, typename _Alloc>
- void
- basic_string<_CharT, _Traits, _Alloc>::
- reserve(size_type __res)
- {
- const size_type __capacity = capacity();
-
- // _GLIBCXX_RESOLVE_LIB_DEFECTS
- // 2968. Inconsistencies between basic_string reserve and
- // vector/unordered_map/unordered_set reserve functions
- // P0966 reserve should not shrink
- if (__res <= __capacity)
- {
- if (!_M_rep()->_M_is_shared())
- return;
-
- // unshare, but keep same capacity
- __res = __capacity;
- }
-
- const allocator_type __a = get_allocator();
- _CharT* __tmp = _M_rep()->_M_clone(__a, __res - this->size());
- _M_rep()->_M_dispose(__a);
- _M_data(__tmp);
- }
-
- template<typename _CharT, typename _Traits, typename _Alloc>
- void
- basic_string<_CharT, _Traits, _Alloc>::
- swap(basic_string& __s)
- _GLIBCXX_NOEXCEPT_IF(allocator_traits<_Alloc>::is_always_equal::value)
- {
- if (_M_rep()->_M_is_leaked())
- _M_rep()->_M_set_sharable();
- if (__s._M_rep()->_M_is_leaked())
- __s._M_rep()->_M_set_sharable();
- if (this->get_allocator() == __s.get_allocator())
- {
- _CharT* __tmp = _M_data();
- _M_data(__s._M_data());
- __s._M_data(__tmp);
- }
- // The code below can usually be optimized away.
- else
- {
- const basic_string __tmp1(_M_ibegin(), _M_iend(),
- __s.get_allocator());
- const basic_string __tmp2(__s._M_ibegin(), __s._M_iend(),
- this->get_allocator());
- *this = __tmp2;
- __s = __tmp1;
- }
- }
-
- template<typename _CharT, typename _Traits, typename _Alloc>
- typename basic_string<_CharT, _Traits, _Alloc>::_Rep*
- basic_string<_CharT, _Traits, _Alloc>::_Rep::
- _S_create(size_type __capacity, size_type __old_capacity,
- const _Alloc& __alloc)
- {
- // _GLIBCXX_RESOLVE_LIB_DEFECTS
- // 83. String::npos vs. string::max_size()
- if (__capacity > _S_max_size)
- __throw_length_error(__N("basic_string::_S_create"));
-
- // The standard places no restriction on allocating more memory
- // than is strictly needed within this layer at the moment or as
- // requested by an explicit application call to reserve(n).
-
- // Many malloc implementations perform quite poorly when an
- // application attempts to allocate memory in a stepwise fashion
- // growing each allocation size by only 1 char. Additionally,
- // it makes little sense to allocate less linear memory than the
- // natural blocking size of the malloc implementation.
- // Unfortunately, we would need a somewhat low-level calculation
- // with tuned parameters to get this perfect for any particular
- // malloc implementation. Fortunately, generalizations about
- // common features seen among implementations seems to suffice.
-
- // __pagesize need not match the actual VM page size for good
- // results in practice, thus we pick a common value on the low
- // side. __malloc_header_size is an estimate of the amount of
- // overhead per memory allocation (in practice seen N * sizeof
- // (void*) where N is 0, 2 or 4). According to folklore,
- // picking this value on the high side is better than
- // low-balling it (especially when this algorithm is used with
- // malloc implementations that allocate memory blocks rounded up
- // to a size which is a power of 2).
- const size_type __pagesize = 4096;
- const size_type __malloc_header_size = 4 * sizeof(void*);
-
- // The below implements an exponential growth policy, necessary to
- // meet amortized linear time requirements of the library: see
- // http://gcc.gnu.org/ml/libstdc++/2001-07/msg00085.html.
- // It's active for allocations requiring an amount of memory above
- // system pagesize. This is consistent with the requirements of the
- // standard: http://gcc.gnu.org/ml/libstdc++/2001-07/msg00130.html
- if (__capacity > __old_capacity && __capacity < 2 * __old_capacity)
- __capacity = 2 * __old_capacity;
-
- // NB: Need an array of char_type[__capacity], plus a terminating
- // null char_type() element, plus enough for the _Rep data structure.
- // Whew. Seemingly so needy, yet so elemental.
- size_type __size = (__capacity + 1) * sizeof(_CharT) + sizeof(_Rep);
-
- const size_type __adj_size = __size + __malloc_header_size;
- if (__adj_size > __pagesize && __capacity > __old_capacity)
- {
- const size_type __extra = __pagesize - __adj_size % __pagesize;
- __capacity += __extra / sizeof(_CharT);
- // Never allocate a string bigger than _S_max_size.
- if (__capacity > _S_max_size)
- __capacity = _S_max_size;
- __size = (__capacity + 1) * sizeof(_CharT) + sizeof(_Rep);
- }
-
- // NB: Might throw, but no worries about a leak, mate: _Rep()
- // does not throw.
- void* __place = _Raw_bytes_alloc(__alloc).allocate(__size);
- _Rep *__p = new (__place) _Rep;
- __p->_M_capacity = __capacity;
- // ABI compatibility - 3.4.x set in _S_create both
- // _M_refcount and _M_length. All callers of _S_create
- // in basic_string.tcc then set just _M_length.
- // In 4.0.x and later both _M_refcount and _M_length
- // are initialized in the callers, unfortunately we can
- // have 3.4.x compiled code with _S_create callers inlined
- // calling 4.0.x+ _S_create.
- __p->_M_set_sharable();
- return __p;
- }
-
- template<typename _CharT, typename _Traits, typename _Alloc>
- _CharT*
- basic_string<_CharT, _Traits, _Alloc>::_Rep::
- _M_clone(const _Alloc& __alloc, size_type __res)
- {
- // Requested capacity of the clone.
- const size_type __requested_cap = this->_M_length + __res;
- _Rep* __r = _Rep::_S_create(__requested_cap, this->_M_capacity,
- __alloc);
- if (this->_M_length)
- _M_copy(__r->_M_refdata(), _M_refdata(), this->_M_length);
-
- __r->_M_set_length_and_sharable(this->_M_length);
- return __r->_M_refdata();
- }
-
- template<typename _CharT, typename _Traits, typename _Alloc>
- void
- basic_string<_CharT, _Traits, _Alloc>::
- resize(size_type __n, _CharT __c)
- {
- const size_type __size = this->size();
- _M_check_length(__size, __n, "basic_string::resize");
- if (__size < __n)
- this->append(__n - __size, __c);
- else if (__n < __size)
- this->erase(__n);
- // else nothing (in particular, avoid calling _M_mutate() unnecessarily.)
- }
-
- template<typename _CharT, typename _Traits, typename _Alloc>
- template<typename _InputIterator>
- basic_string<_CharT, _Traits, _Alloc>&
- basic_string<_CharT, _Traits, _Alloc>::
- _M_replace_dispatch(iterator __i1, iterator __i2, _InputIterator __k1,
- _InputIterator __k2, __false_type)
- {
- const basic_string __s(__k1, __k2);
- const size_type __n1 = __i2 - __i1;
- _M_check_length(__n1, __s.size(), "basic_string::_M_replace_dispatch");
- return _M_replace_safe(__i1 - _M_ibegin(), __n1, __s._M_data(),
- __s.size());
- }
-
- template<typename _CharT, typename _Traits, typename _Alloc>
- basic_string<_CharT, _Traits, _Alloc>&
- basic_string<_CharT, _Traits, _Alloc>::
- _M_replace_aux(size_type __pos1, size_type __n1, size_type __n2,
- _CharT __c)
- {
- _M_check_length(__n1, __n2, "basic_string::_M_replace_aux");
- _M_mutate(__pos1, __n1, __n2);
- if (__n2)
- _M_assign(_M_data() + __pos1, __n2, __c);
- return *this;
- }
-
- template<typename _CharT, typename _Traits, typename _Alloc>
- basic_string<_CharT, _Traits, _Alloc>&
- basic_string<_CharT, _Traits, _Alloc>::
- _M_replace_safe(size_type __pos1, size_type __n1, const _CharT* __s,
- size_type __n2)
- {
- _M_mutate(__pos1, __n1, __n2);
- if (__n2)
- _M_copy(_M_data() + __pos1, __s, __n2);
- return *this;
- }
-
- template<typename _CharT, typename _Traits, typename _Alloc>
- void
- basic_string<_CharT, _Traits, _Alloc>::
- reserve()
- {
-#if __cpp_exceptions
- if (length() < capacity() || _M_rep()->_M_is_shared())
- try
- {
- const allocator_type __a = get_allocator();
- _CharT* __tmp = _M_rep()->_M_clone(__a);
- _M_rep()->_M_dispose(__a);
- _M_data(__tmp);
- }
- catch (const __cxxabiv1::__forced_unwind&)
- { throw; }
- catch (...)
- { /* swallow the exception */ }
-#endif
- }
-
- template<typename _CharT, typename _Traits, typename _Alloc>
- typename basic_string<_CharT, _Traits, _Alloc>::size_type
- basic_string<_CharT, _Traits, _Alloc>::
- copy(_CharT* __s, size_type __n, size_type __pos) const
- {
- _M_check(__pos, "basic_string::copy");
- __n = _M_limit(__pos, __n);
- __glibcxx_requires_string_len(__s, __n);
- if (__n)
- _M_copy(__s, _M_data() + __pos, __n);
- // 21.3.5.7 par 3: do not append null. (good.)
- return __n;
- }
-#endif // !_GLIBCXX_USE_CXX11_ABI
+#endif // _GLIBCXX_USE_CXX11_ABI
template<typename _CharT, typename _Traits, typename _Alloc>
basic_string<_CharT, _Traits, _Alloc>
--- /dev/null
+// Definition of gcc4-compatible Copy-on-Write basic_string -*- C++ -*-
+
+// Copyright (C) 1997-2021 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library. This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+
+// Under Section 7 of GPL version 3, you are granted additional
+// permissions described in the GCC Runtime Library Exception, version
+// 3.1, as published by the Free Software Foundation.
+
+// You should have received a copy of the GNU General Public License and
+// a copy of the GCC Runtime Library Exception along with this program;
+// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
+// <http://www.gnu.org/licenses/>.
+
+/** @file bits/cow_string.h
+ * This is an internal header file, included by other library headers.
+ * Do not attempt to use it directly. @headername{string}
+ *
+ * Defines the reference-counted COW string implentation.
+ */
+
+#ifndef _COW_STRING_H
+#define _COW_STRING_H 1
+
+#if ! _GLIBCXX_USE_CXX11_ABI
+
+#ifdef __cpp_lib_is_constant_evaluated
+// Support P1032R1 in C++20 (but not P0980R1 yet).
+# define __cpp_lib_constexpr_string 201811L
+#elif __cplusplus >= 201703L && _GLIBCXX_HAVE_BUILTIN_IS_CONSTANT_EVALUATED
+// Support P0426R1 changes to char_traits in C++17.
+# define __cpp_lib_constexpr_string 201611L
+#endif
+
+namespace std _GLIBCXX_VISIBILITY(default)
+{
+_GLIBCXX_BEGIN_NAMESPACE_VERSION
+
+ /**
+ * @class basic_string basic_string.h <string>
+ * @brief Managing sequences of characters and character-like objects.
+ *
+ * @ingroup strings
+ * @ingroup sequences
+ *
+ * @tparam _CharT Type of character
+ * @tparam _Traits Traits for character type, defaults to
+ * char_traits<_CharT>.
+ * @tparam _Alloc Allocator type, defaults to allocator<_CharT>.
+ *
+ * Meets the requirements of a <a href="tables.html#65">container</a>, a
+ * <a href="tables.html#66">reversible container</a>, and a
+ * <a href="tables.html#67">sequence</a>. Of the
+ * <a href="tables.html#68">optional sequence requirements</a>, only
+ * @c push_back, @c at, and @c %array access are supported.
+ *
+ * @doctodo
+ *
+ *
+ * Documentation? What's that?
+ * Nathan Myers <ncm@cantrip.org>.
+ *
+ * A string looks like this:
+ *
+ * @code
+ * [_Rep]
+ * _M_length
+ * [basic_string<char_type>] _M_capacity
+ * _M_dataplus _M_refcount
+ * _M_p ----------------> unnamed array of char_type
+ * @endcode
+ *
+ * Where the _M_p points to the first character in the string, and
+ * you cast it to a pointer-to-_Rep and subtract 1 to get a
+ * pointer to the header.
+ *
+ * This approach has the enormous advantage that a string object
+ * requires only one allocation. All the ugliness is confined
+ * within a single %pair of inline functions, which each compile to
+ * a single @a add instruction: _Rep::_M_data(), and
+ * string::_M_rep(); and the allocation function which gets a
+ * block of raw bytes and with room enough and constructs a _Rep
+ * object at the front.
+ *
+ * The reason you want _M_data pointing to the character %array and
+ * not the _Rep is so that the debugger can see the string
+ * contents. (Probably we should add a non-inline member to get
+ * the _Rep for the debugger to use, so users can check the actual
+ * string length.)
+ *
+ * Note that the _Rep object is a POD so that you can have a
+ * static <em>empty string</em> _Rep object already @a constructed before
+ * static constructors have run. The reference-count encoding is
+ * chosen so that a 0 indicates one reference, so you never try to
+ * destroy the empty-string _Rep object.
+ *
+ * All but the last paragraph is considered pretty conventional
+ * for a C++ string implementation.
+ */
+ // 21.3 Template class basic_string
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ class basic_string
+ {
+ typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template
+ rebind<_CharT>::other _CharT_alloc_type;
+ typedef __gnu_cxx::__alloc_traits<_CharT_alloc_type> _CharT_alloc_traits;
+
+ // Types:
+ public:
+ typedef _Traits traits_type;
+ typedef typename _Traits::char_type value_type;
+ typedef _Alloc allocator_type;
+ typedef typename _CharT_alloc_traits::size_type size_type;
+ typedef typename _CharT_alloc_traits::difference_type difference_type;
+#if __cplusplus < 201103L
+ typedef typename _CharT_alloc_type::reference reference;
+ typedef typename _CharT_alloc_type::const_reference const_reference;
+#else
+ typedef value_type& reference;
+ typedef const value_type& const_reference;
+#endif
+ typedef typename _CharT_alloc_traits::pointer pointer;
+ typedef typename _CharT_alloc_traits::const_pointer const_pointer;
+ typedef __gnu_cxx::__normal_iterator<pointer, basic_string> iterator;
+ typedef __gnu_cxx::__normal_iterator<const_pointer, basic_string>
+ const_iterator;
+ typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
+ typedef std::reverse_iterator<iterator> reverse_iterator;
+
+ protected:
+ // type used for positions in insert, erase etc.
+ typedef iterator __const_iterator;
+
+ private:
+ // _Rep: string representation
+ // Invariants:
+ // 1. String really contains _M_length + 1 characters: due to 21.3.4
+ // must be kept null-terminated.
+ // 2. _M_capacity >= _M_length
+ // Allocated memory is always (_M_capacity + 1) * sizeof(_CharT).
+ // 3. _M_refcount has three states:
+ // -1: leaked, one reference, no ref-copies allowed, non-const.
+ // 0: one reference, non-const.
+ // n>0: n + 1 references, operations require a lock, const.
+ // 4. All fields==0 is an empty string, given the extra storage
+ // beyond-the-end for a null terminator; thus, the shared
+ // empty string representation needs no constructor.
+
+ struct _Rep_base
+ {
+ size_type _M_length;
+ size_type _M_capacity;
+ _Atomic_word _M_refcount;
+ };
+
+ struct _Rep : _Rep_base
+ {
+ // Types:
+ typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template
+ rebind<char>::other _Raw_bytes_alloc;
+
+ // (Public) Data members:
+
+ // The maximum number of individual char_type elements of an
+ // individual string is determined by _S_max_size. This is the
+ // value that will be returned by max_size(). (Whereas npos
+ // is the maximum number of bytes the allocator can allocate.)
+ // If one was to divvy up the theoretical largest size string,
+ // with a terminating character and m _CharT elements, it'd
+ // look like this:
+ // npos = sizeof(_Rep) + (m * sizeof(_CharT)) + sizeof(_CharT)
+ // Solving for m:
+ // m = ((npos - sizeof(_Rep))/sizeof(CharT)) - 1
+ // In addition, this implementation quarters this amount.
+ static const size_type _S_max_size;
+ static const _CharT _S_terminal;
+
+ // The following storage is init'd to 0 by the linker, resulting
+ // (carefully) in an empty string with one reference.
+ static size_type _S_empty_rep_storage[];
+
+ static _Rep&
+ _S_empty_rep() _GLIBCXX_NOEXCEPT
+ {
+ // NB: Mild hack to avoid strict-aliasing warnings. Note that
+ // _S_empty_rep_storage is never modified and the punning should
+ // be reasonably safe in this case.
+ void* __p = reinterpret_cast<void*>(&_S_empty_rep_storage);
+ return *reinterpret_cast<_Rep*>(__p);
+ }
+
+ bool
+ _M_is_leaked() const _GLIBCXX_NOEXCEPT
+ {
+#if defined(__GTHREADS)
+ // _M_refcount is mutated concurrently by _M_refcopy/_M_dispose,
+ // so we need to use an atomic load. However, _M_is_leaked
+ // predicate does not change concurrently (i.e. the string is either
+ // leaked or not), so a relaxed load is enough.
+ return __atomic_load_n(&this->_M_refcount, __ATOMIC_RELAXED) < 0;
+#else
+ return this->_M_refcount < 0;
+#endif
+ }
+
+ bool
+ _M_is_shared() const _GLIBCXX_NOEXCEPT
+ {
+#if defined(__GTHREADS)
+ // _M_refcount is mutated concurrently by _M_refcopy/_M_dispose,
+ // so we need to use an atomic load. Another thread can drop last
+ // but one reference concurrently with this check, so we need this
+ // load to be acquire to synchronize with release fetch_and_add in
+ // _M_dispose.
+ return __atomic_load_n(&this->_M_refcount, __ATOMIC_ACQUIRE) > 0;
+#else
+ return this->_M_refcount > 0;
+#endif
+ }
+
+ void
+ _M_set_leaked() _GLIBCXX_NOEXCEPT
+ { this->_M_refcount = -1; }
+
+ void
+ _M_set_sharable() _GLIBCXX_NOEXCEPT
+ { this->_M_refcount = 0; }
+
+ void
+ _M_set_length_and_sharable(size_type __n) _GLIBCXX_NOEXCEPT
+ {
+#if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
+ if (__builtin_expect(this != &_S_empty_rep(), false))
+#endif
+ {
+ this->_M_set_sharable(); // One reference.
+ this->_M_length = __n;
+ traits_type::assign(this->_M_refdata()[__n], _S_terminal);
+ // grrr. (per 21.3.4)
+ // You cannot leave those LWG people alone for a second.
+ }
+ }
+
+ _CharT*
+ _M_refdata() throw()
+ { return reinterpret_cast<_CharT*>(this + 1); }
+
+ _CharT*
+ _M_grab(const _Alloc& __alloc1, const _Alloc& __alloc2)
+ {
+ return (!_M_is_leaked() && __alloc1 == __alloc2)
+ ? _M_refcopy() : _M_clone(__alloc1);
+ }
+
+ // Create & Destroy
+ static _Rep*
+ _S_create(size_type, size_type, const _Alloc&);
+
+ void
+ _M_dispose(const _Alloc& __a) _GLIBCXX_NOEXCEPT
+ {
+#if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
+ if (__builtin_expect(this != &_S_empty_rep(), false))
+#endif
+ {
+ // Be race-detector-friendly. For more info see bits/c++config.
+ _GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE(&this->_M_refcount);
+ // Decrement of _M_refcount is acq_rel, because:
+ // - all but last decrements need to release to synchronize with
+ // the last decrement that will delete the object.
+ // - the last decrement needs to acquire to synchronize with
+ // all the previous decrements.
+ // - last but one decrement needs to release to synchronize with
+ // the acquire load in _M_is_shared that will conclude that
+ // the object is not shared anymore.
+ if (__gnu_cxx::__exchange_and_add_dispatch(&this->_M_refcount,
+ -1) <= 0)
+ {
+ _GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER(&this->_M_refcount);
+ _M_destroy(__a);
+ }
+ }
+ } // XXX MT
+
+ void
+ _M_destroy(const _Alloc&) throw();
+
+ _CharT*
+ _M_refcopy() throw()
+ {
+#if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
+ if (__builtin_expect(this != &_S_empty_rep(), false))
+#endif
+ __gnu_cxx::__atomic_add_dispatch(&this->_M_refcount, 1);
+ return _M_refdata();
+ } // XXX MT
+
+ _CharT*
+ _M_clone(const _Alloc&, size_type __res = 0);
+ };
+
+ // Use empty-base optimization: http://www.cantrip.org/emptyopt.html
+ struct _Alloc_hider : _Alloc
+ {
+ _Alloc_hider(_CharT* __dat, const _Alloc& __a) _GLIBCXX_NOEXCEPT
+ : _Alloc(__a), _M_p(__dat) { }
+
+ _CharT* _M_p; // The actual data.
+ };
+
+ public:
+ // Data Members (public):
+ // NB: This is an unsigned type, and thus represents the maximum
+ // size that the allocator can hold.
+ /// Value returned by various member functions when they fail.
+ static const size_type npos = static_cast<size_type>(-1);
+
+ private:
+ // Data Members (private):
+ mutable _Alloc_hider _M_dataplus;
+
+ _CharT*
+ _M_data() const _GLIBCXX_NOEXCEPT
+ { return _M_dataplus._M_p; }
+
+ _CharT*
+ _M_data(_CharT* __p) _GLIBCXX_NOEXCEPT
+ { return (_M_dataplus._M_p = __p); }
+
+ _Rep*
+ _M_rep() const _GLIBCXX_NOEXCEPT
+ { return &((reinterpret_cast<_Rep*> (_M_data()))[-1]); }
+
+ // For the internal use we have functions similar to `begin'/`end'
+ // but they do not call _M_leak.
+ iterator
+ _M_ibegin() const _GLIBCXX_NOEXCEPT
+ { return iterator(_M_data()); }
+
+ iterator
+ _M_iend() const _GLIBCXX_NOEXCEPT
+ { return iterator(_M_data() + this->size()); }
+
+ void
+ _M_leak() // for use in begin() & non-const op[]
+ {
+ if (!_M_rep()->_M_is_leaked())
+ _M_leak_hard();
+ }
+
+ size_type
+ _M_check(size_type __pos, const char* __s) const
+ {
+ if (__pos > this->size())
+ __throw_out_of_range_fmt(__N("%s: __pos (which is %zu) > "
+ "this->size() (which is %zu)"),
+ __s, __pos, this->size());
+ return __pos;
+ }
+
+ void
+ _M_check_length(size_type __n1, size_type __n2, const char* __s) const
+ {
+ if (this->max_size() - (this->size() - __n1) < __n2)
+ __throw_length_error(__N(__s));
+ }
+
+ // NB: _M_limit doesn't check for a bad __pos value.
+ size_type
+ _M_limit(size_type __pos, size_type __off) const _GLIBCXX_NOEXCEPT
+ {
+ const bool __testoff = __off < this->size() - __pos;
+ return __testoff ? __off : this->size() - __pos;
+ }
+
+ // True if _Rep and source do not overlap.
+ bool
+ _M_disjunct(const _CharT* __s) const _GLIBCXX_NOEXCEPT
+ {
+ return (less<const _CharT*>()(__s, _M_data())
+ || less<const _CharT*>()(_M_data() + this->size(), __s));
+ }
+
+ // When __n = 1 way faster than the general multichar
+ // traits_type::copy/move/assign.
+ static void
+ _M_copy(_CharT* __d, const _CharT* __s, size_type __n) _GLIBCXX_NOEXCEPT
+ {
+ if (__n == 1)
+ traits_type::assign(*__d, *__s);
+ else
+ traits_type::copy(__d, __s, __n);
+ }
+
+ static void
+ _M_move(_CharT* __d, const _CharT* __s, size_type __n) _GLIBCXX_NOEXCEPT
+ {
+ if (__n == 1)
+ traits_type::assign(*__d, *__s);
+ else
+ traits_type::move(__d, __s, __n);
+ }
+
+ static void
+ _M_assign(_CharT* __d, size_type __n, _CharT __c) _GLIBCXX_NOEXCEPT
+ {
+ if (__n == 1)
+ traits_type::assign(*__d, __c);
+ else
+ traits_type::assign(__d, __n, __c);
+ }
+
+ // _S_copy_chars is a separate template to permit specialization
+ // to optimize for the common case of pointers as iterators.
+ template<class _Iterator>
+ static void
+ _S_copy_chars(_CharT* __p, _Iterator __k1, _Iterator __k2)
+ {
+ for (; __k1 != __k2; ++__k1, (void)++__p)
+ traits_type::assign(*__p, *__k1); // These types are off.
+ }
+
+ static void
+ _S_copy_chars(_CharT* __p, iterator __k1, iterator __k2) _GLIBCXX_NOEXCEPT
+ { _S_copy_chars(__p, __k1.base(), __k2.base()); }
+
+ static void
+ _S_copy_chars(_CharT* __p, const_iterator __k1, const_iterator __k2)
+ _GLIBCXX_NOEXCEPT
+ { _S_copy_chars(__p, __k1.base(), __k2.base()); }
+
+ static void
+ _S_copy_chars(_CharT* __p, _CharT* __k1, _CharT* __k2) _GLIBCXX_NOEXCEPT
+ { _M_copy(__p, __k1, __k2 - __k1); }
+
+ static void
+ _S_copy_chars(_CharT* __p, const _CharT* __k1, const _CharT* __k2)
+ _GLIBCXX_NOEXCEPT
+ { _M_copy(__p, __k1, __k2 - __k1); }
+
+ static int
+ _S_compare(size_type __n1, size_type __n2) _GLIBCXX_NOEXCEPT
+ {
+ const difference_type __d = difference_type(__n1 - __n2);
+
+ if (__d > __gnu_cxx::__numeric_traits<int>::__max)
+ return __gnu_cxx::__numeric_traits<int>::__max;
+ else if (__d < __gnu_cxx::__numeric_traits<int>::__min)
+ return __gnu_cxx::__numeric_traits<int>::__min;
+ else
+ return int(__d);
+ }
+
+ void
+ _M_mutate(size_type __pos, size_type __len1, size_type __len2);
+
+ void
+ _M_leak_hard();
+
+ static _Rep&
+ _S_empty_rep() _GLIBCXX_NOEXCEPT
+ { return _Rep::_S_empty_rep(); }
+
+#if __cplusplus >= 201703L
+ // A helper type for avoiding boiler-plate.
+ typedef basic_string_view<_CharT, _Traits> __sv_type;
+
+ template<typename _Tp, typename _Res>
+ using _If_sv = enable_if_t<
+ __and_<is_convertible<const _Tp&, __sv_type>,
+ __not_<is_convertible<const _Tp*, const basic_string*>>,
+ __not_<is_convertible<const _Tp&, const _CharT*>>>::value,
+ _Res>;
+
+ // Allows an implicit conversion to __sv_type.
+ static __sv_type
+ _S_to_string_view(__sv_type __svt) noexcept
+ { return __svt; }
+
+ // Wraps a string_view by explicit conversion and thus
+ // allows to add an internal constructor that does not
+ // participate in overload resolution when a string_view
+ // is provided.
+ struct __sv_wrapper
+ {
+ explicit __sv_wrapper(__sv_type __sv) noexcept : _M_sv(__sv) { }
+ __sv_type _M_sv;
+ };
+
+ /**
+ * @brief Only internally used: Construct string from a string view
+ * wrapper.
+ * @param __svw string view wrapper.
+ * @param __a Allocator to use.
+ */
+ explicit
+ basic_string(__sv_wrapper __svw, const _Alloc& __a)
+ : basic_string(__svw._M_sv.data(), __svw._M_sv.size(), __a) { }
+#endif
+
+ public:
+ // Construct/copy/destroy:
+ // NB: We overload ctors in some cases instead of using default
+ // arguments, per 17.4.4.4 para. 2 item 2.
+
+ /**
+ * @brief Default constructor creates an empty string.
+ */
+ basic_string()
+#if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
+ _GLIBCXX_NOEXCEPT
+ : _M_dataplus(_S_empty_rep()._M_refdata(), _Alloc())
+#else
+ : _M_dataplus(_S_construct(size_type(), _CharT(), _Alloc()), _Alloc())
+#endif
+ { }
+
+ /**
+ * @brief Construct an empty string using allocator @a a.
+ */
+ explicit
+ basic_string(const _Alloc& __a)
+ : _M_dataplus(_S_construct(size_type(), _CharT(), __a), __a)
+ { }
+
+ // NB: per LWG issue 42, semantics different from IS:
+ /**
+ * @brief Construct string with copy of value of @a str.
+ * @param __str Source string.
+ */
+ basic_string(const basic_string& __str)
+ : _M_dataplus(__str._M_rep()->_M_grab(_Alloc(__str.get_allocator()),
+ __str.get_allocator()),
+ __str.get_allocator())
+ { }
+
+ // _GLIBCXX_RESOLVE_LIB_DEFECTS
+ // 2583. no way to supply an allocator for basic_string(str, pos)
+ /**
+ * @brief Construct string as copy of a substring.
+ * @param __str Source string.
+ * @param __pos Index of first character to copy from.
+ * @param __a Allocator to use.
+ */
+ basic_string(const basic_string& __str, size_type __pos,
+ const _Alloc& __a = _Alloc());
+
+ /**
+ * @brief Construct string as copy of a substring.
+ * @param __str Source string.
+ * @param __pos Index of first character to copy from.
+ * @param __n Number of characters to copy.
+ */
+ basic_string(const basic_string& __str, size_type __pos,
+ size_type __n);
+ /**
+ * @brief Construct string as copy of a substring.
+ * @param __str Source string.
+ * @param __pos Index of first character to copy from.
+ * @param __n Number of characters to copy.
+ * @param __a Allocator to use.
+ */
+ basic_string(const basic_string& __str, size_type __pos,
+ size_type __n, const _Alloc& __a);
+
+ /**
+ * @brief Construct string initialized by a character %array.
+ * @param __s Source character %array.
+ * @param __n Number of characters to copy.
+ * @param __a Allocator to use (default is default allocator).
+ *
+ * NB: @a __s must have at least @a __n characters, '\\0'
+ * has no special meaning.
+ */
+ basic_string(const _CharT* __s, size_type __n,
+ const _Alloc& __a = _Alloc())
+ : _M_dataplus(_S_construct(__s, __s + __n, __a), __a)
+ { }
+
+ /**
+ * @brief Construct string as copy of a C string.
+ * @param __s Source C string.
+ * @param __a Allocator to use (default is default allocator).
+ */
+#if __cpp_deduction_guides && ! defined _GLIBCXX_DEFINING_STRING_INSTANTIATIONS
+ // _GLIBCXX_RESOLVE_LIB_DEFECTS
+ // 3076. basic_string CTAD ambiguity
+ template<typename = _RequireAllocator<_Alloc>>
+#endif
+ basic_string(const _CharT* __s, const _Alloc& __a = _Alloc())
+ : _M_dataplus(_S_construct(__s, __s ? __s + traits_type::length(__s) :
+ __s + npos, __a), __a)
+ { }
+
+ /**
+ * @brief Construct string as multiple characters.
+ * @param __n Number of characters.
+ * @param __c Character to use.
+ * @param __a Allocator to use (default is default allocator).
+ */
+ basic_string(size_type __n, _CharT __c, const _Alloc& __a = _Alloc())
+ : _M_dataplus(_S_construct(__n, __c, __a), __a)
+ { }
+
+#if __cplusplus >= 201103L
+ /**
+ * @brief Move construct string.
+ * @param __str Source string.
+ *
+ * The newly-created string contains the exact contents of @a __str.
+ * @a __str is a valid, but unspecified string.
+ */
+ basic_string(basic_string&& __str)
+#if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
+ noexcept // FIXME C++11: should always be noexcept.
+#endif
+ : _M_dataplus(std::move(__str._M_dataplus))
+ {
+#if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
+ __str._M_data(_S_empty_rep()._M_refdata());
+#else
+ __str._M_data(_S_construct(size_type(), _CharT(), get_allocator()));
+#endif
+ }
+
+ /**
+ * @brief Construct string from an initializer %list.
+ * @param __l std::initializer_list of characters.
+ * @param __a Allocator to use (default is default allocator).
+ */
+ basic_string(initializer_list<_CharT> __l, const _Alloc& __a = _Alloc())
+ : _M_dataplus(_S_construct(__l.begin(), __l.end(), __a), __a)
+ { }
+
+ basic_string(const basic_string& __str, const _Alloc& __a)
+ : _M_dataplus(__str._M_rep()->_M_grab(__a, __str.get_allocator()), __a)
+ { }
+
+ basic_string(basic_string&& __str, const _Alloc& __a)
+ : _M_dataplus(__str._M_data(), __a)
+ {
+ if (__a == __str.get_allocator())
+ {
+#if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
+ __str._M_data(_S_empty_rep()._M_refdata());
+#else
+ __str._M_data(_S_construct(size_type(), _CharT(), __a));
+#endif
+ }
+ else
+ _M_dataplus._M_p = _S_construct(__str.begin(), __str.end(), __a);
+ }
+#endif // C++11
+
+ /**
+ * @brief Construct string as copy of a range.
+ * @param __beg Start of range.
+ * @param __end End of range.
+ * @param __a Allocator to use (default is default allocator).
+ */
+ template<class _InputIterator>
+ basic_string(_InputIterator __beg, _InputIterator __end,
+ const _Alloc& __a = _Alloc())
+ : _M_dataplus(_S_construct(__beg, __end, __a), __a)
+ { }
+
+#if __cplusplus >= 201703L
+ /**
+ * @brief Construct string from a substring of a string_view.
+ * @param __t Source object convertible to string view.
+ * @param __pos The index of the first character to copy from __t.
+ * @param __n The number of characters to copy from __t.
+ * @param __a Allocator to use.
+ */
+ template<typename _Tp, typename = _If_sv<_Tp, void>>
+ basic_string(const _Tp& __t, size_type __pos, size_type __n,
+ const _Alloc& __a = _Alloc())
+ : basic_string(_S_to_string_view(__t).substr(__pos, __n), __a) { }
+
+ /**
+ * @brief Construct string from a string_view.
+ * @param __t Source object convertible to string view.
+ * @param __a Allocator to use (default is default allocator).
+ */
+ template<typename _Tp, typename = _If_sv<_Tp, void>>
+ explicit
+ basic_string(const _Tp& __t, const _Alloc& __a = _Alloc())
+ : basic_string(__sv_wrapper(_S_to_string_view(__t)), __a) { }
+#endif // C++17
+
+ /**
+ * @brief Destroy the string instance.
+ */
+ ~basic_string() _GLIBCXX_NOEXCEPT
+ { _M_rep()->_M_dispose(this->get_allocator()); }
+
+ /**
+ * @brief Assign the value of @a str to this string.
+ * @param __str Source string.
+ */
+ basic_string&
+ operator=(const basic_string& __str)
+ { return this->assign(__str); }
+
+ /**
+ * @brief Copy contents of @a s into this string.
+ * @param __s Source null-terminated string.
+ */
+ basic_string&
+ operator=(const _CharT* __s)
+ { return this->assign(__s); }
+
+ /**
+ * @brief Set value to string of length 1.
+ * @param __c Source character.
+ *
+ * Assigning to a character makes this string length 1 and
+ * (*this)[0] == @a c.
+ */
+ basic_string&
+ operator=(_CharT __c)
+ {
+ this->assign(1, __c);
+ return *this;
+ }
+
+#if __cplusplus >= 201103L
+ /**
+ * @brief Move assign the value of @a str to this string.
+ * @param __str Source string.
+ *
+ * The contents of @a str are moved into this string (without copying).
+ * @a str is a valid, but unspecified string.
+ */
+ basic_string&
+ operator=(basic_string&& __str)
+ _GLIBCXX_NOEXCEPT_IF(allocator_traits<_Alloc>::is_always_equal::value)
+ {
+ // NB: DR 1204.
+ this->swap(__str);
+ return *this;
+ }
+
+ /**
+ * @brief Set value to string constructed from initializer %list.
+ * @param __l std::initializer_list.
+ */
+ basic_string&
+ operator=(initializer_list<_CharT> __l)
+ {
+ this->assign(__l.begin(), __l.size());
+ return *this;
+ }
+#endif // C++11
+
+#if __cplusplus >= 201703L
+ /**
+ * @brief Set value to string constructed from a string_view.
+ * @param __svt An object convertible to string_view.
+ */
+ template<typename _Tp>
+ _If_sv<_Tp, basic_string&>
+ operator=(const _Tp& __svt)
+ { return this->assign(__svt); }
+
+ /**
+ * @brief Convert to a string_view.
+ * @return A string_view.
+ */
+ operator __sv_type() const noexcept
+ { return __sv_type(data(), size()); }
+#endif // C++17
+
+ // Iterators:
+ /**
+ * Returns a read/write iterator that points to the first character in
+ * the %string. Unshares the string.
+ */
+ iterator
+ begin() // FIXME C++11: should be noexcept.
+ {
+ _M_leak();
+ return iterator(_M_data());
+ }
+
+ /**
+ * Returns a read-only (constant) iterator that points to the first
+ * character in the %string.
+ */
+ const_iterator
+ begin() const _GLIBCXX_NOEXCEPT
+ { return const_iterator(_M_data()); }
+
+ /**
+ * Returns a read/write iterator that points one past the last
+ * character in the %string. Unshares the string.
+ */
+ iterator
+ end() // FIXME C++11: should be noexcept.
+ {
+ _M_leak();
+ return iterator(_M_data() + this->size());
+ }
+
+ /**
+ * Returns a read-only (constant) iterator that points one past the
+ * last character in the %string.
+ */
+ const_iterator
+ end() const _GLIBCXX_NOEXCEPT
+ { return const_iterator(_M_data() + this->size()); }
+
+ /**
+ * Returns a read/write reverse iterator that points to the last
+ * character in the %string. Iteration is done in reverse element
+ * order. Unshares the string.
+ */
+ reverse_iterator
+ rbegin() // FIXME C++11: should be noexcept.
+ { return reverse_iterator(this->end()); }
+
+ /**
+ * Returns a read-only (constant) reverse iterator that points
+ * to the last character in the %string. Iteration is done in
+ * reverse element order.
+ */
+ const_reverse_iterator
+ rbegin() const _GLIBCXX_NOEXCEPT
+ { return const_reverse_iterator(this->end()); }
+
+ /**
+ * Returns a read/write reverse iterator that points to one before the
+ * first character in the %string. Iteration is done in reverse
+ * element order. Unshares the string.
+ */
+ reverse_iterator
+ rend() // FIXME C++11: should be noexcept.
+ { return reverse_iterator(this->begin()); }
+
+ /**
+ * Returns a read-only (constant) reverse iterator that points
+ * to one before the first character in the %string. Iteration
+ * is done in reverse element order.
+ */
+ const_reverse_iterator
+ rend() const _GLIBCXX_NOEXCEPT
+ { return const_reverse_iterator(this->begin()); }
+
+#if __cplusplus >= 201103L
+ /**
+ * Returns a read-only (constant) iterator that points to the first
+ * character in the %string.
+ */
+ const_iterator
+ cbegin() const noexcept
+ { return const_iterator(this->_M_data()); }
+
+ /**
+ * Returns a read-only (constant) iterator that points one past the
+ * last character in the %string.
+ */
+ const_iterator
+ cend() const noexcept
+ { return const_iterator(this->_M_data() + this->size()); }
+
+ /**
+ * Returns a read-only (constant) reverse iterator that points
+ * to the last character in the %string. Iteration is done in
+ * reverse element order.
+ */
+ const_reverse_iterator
+ crbegin() const noexcept
+ { return const_reverse_iterator(this->end()); }
+
+ /**
+ * Returns a read-only (constant) reverse iterator that points
+ * to one before the first character in the %string. Iteration
+ * is done in reverse element order.
+ */
+ const_reverse_iterator
+ crend() const noexcept
+ { return const_reverse_iterator(this->begin()); }
+#endif
+
+ public:
+ // Capacity:
+ /// Returns the number of characters in the string, not including any
+ /// null-termination.
+ size_type
+ size() const _GLIBCXX_NOEXCEPT
+ { return _M_rep()->_M_length; }
+
+ /// Returns the number of characters in the string, not including any
+ /// null-termination.
+ size_type
+ length() const _GLIBCXX_NOEXCEPT
+ { return _M_rep()->_M_length; }
+
+ /// Returns the size() of the largest possible %string.
+ size_type
+ max_size() const _GLIBCXX_NOEXCEPT
+ { return _Rep::_S_max_size; }
+
+ /**
+ * @brief Resizes the %string to the specified number of characters.
+ * @param __n Number of characters the %string should contain.
+ * @param __c Character to fill any new elements.
+ *
+ * This function will %resize the %string to the specified
+ * number of characters. If the number is smaller than the
+ * %string's current size the %string is truncated, otherwise
+ * the %string is extended and new elements are %set to @a __c.
+ */
+ void
+ resize(size_type __n, _CharT __c);
+
+ /**
+ * @brief Resizes the %string to the specified number of characters.
+ * @param __n Number of characters the %string should contain.
+ *
+ * This function will resize the %string to the specified length. If
+ * the new size is smaller than the %string's current size the %string
+ * is truncated, otherwise the %string is extended and new characters
+ * are default-constructed. For basic types such as char, this means
+ * setting them to 0.
+ */
+ void
+ resize(size_type __n)
+ { this->resize(__n, _CharT()); }
+
+#if __cplusplus >= 201103L
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+ /// A non-binding request to reduce capacity() to size().
+ void
+ shrink_to_fit() noexcept
+ { reserve(); }
+#pragma GCC diagnostic pop
+#endif
+
+ /**
+ * Returns the total number of characters that the %string can hold
+ * before needing to allocate more memory.
+ */
+ size_type
+ capacity() const _GLIBCXX_NOEXCEPT
+ { return _M_rep()->_M_capacity; }
+
+ /**
+ * @brief Attempt to preallocate enough memory for specified number of
+ * characters.
+ * @param __res_arg Number of characters required.
+ * @throw std::length_error If @a __res_arg exceeds @c max_size().
+ *
+ * This function attempts to reserve enough memory for the
+ * %string to hold the specified number of characters. If the
+ * number requested is more than max_size(), length_error is
+ * thrown.
+ *
+ * The advantage of this function is that if optimal code is a
+ * necessity and the user can determine the string length that will be
+ * required, the user can reserve the memory in %advance, and thus
+ * prevent a possible reallocation of memory and copying of %string
+ * data.
+ */
+ void
+ reserve(size_type __res_arg);
+
+ /// Equivalent to shrink_to_fit().
+#if __cplusplus > 201703L
+ [[deprecated("use shrink_to_fit() instead")]]
+#endif
+ void
+ reserve();
+
+ /**
+ * Erases the string, making it empty.
+ */
+#if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
+ void
+ clear() _GLIBCXX_NOEXCEPT
+ {
+ if (_M_rep()->_M_is_shared())
+ {
+ _M_rep()->_M_dispose(this->get_allocator());
+ _M_data(_S_empty_rep()._M_refdata());
+ }
+ else
+ _M_rep()->_M_set_length_and_sharable(0);
+ }
+#else
+ // PR 56166: this should not throw.
+ void
+ clear()
+ { _M_mutate(0, this->size(), 0); }
+#endif
+
+ /**
+ * Returns true if the %string is empty. Equivalent to
+ * <code>*this == ""</code>.
+ */
+ _GLIBCXX_NODISCARD bool
+ empty() const _GLIBCXX_NOEXCEPT
+ { return this->size() == 0; }
+
+ // Element access:
+ /**
+ * @brief Subscript access to the data contained in the %string.
+ * @param __pos The index of the character to access.
+ * @return Read-only (constant) reference to the character.
+ *
+ * This operator allows for easy, array-style, data access.
+ * Note that data access with this operator is unchecked and
+ * out_of_range lookups are not defined. (For checked lookups
+ * see at().)
+ */
+ const_reference
+ operator[] (size_type __pos) const _GLIBCXX_NOEXCEPT
+ {
+ __glibcxx_assert(__pos <= size());
+ return _M_data()[__pos];
+ }
+
+ /**
+ * @brief Subscript access to the data contained in the %string.
+ * @param __pos The index of the character to access.
+ * @return Read/write reference to the character.
+ *
+ * This operator allows for easy, array-style, data access.
+ * Note that data access with this operator is unchecked and
+ * out_of_range lookups are not defined. (For checked lookups
+ * see at().) Unshares the string.
+ */
+ reference
+ operator[](size_type __pos)
+ {
+ // Allow pos == size() both in C++98 mode, as v3 extension,
+ // and in C++11 mode.
+ __glibcxx_assert(__pos <= size());
+ // In pedantic mode be strict in C++98 mode.
+ _GLIBCXX_DEBUG_PEDASSERT(__cplusplus >= 201103L || __pos < size());
+ _M_leak();
+ return _M_data()[__pos];
+ }
+
+ /**
+ * @brief Provides access to the data contained in the %string.
+ * @param __n The index of the character to access.
+ * @return Read-only (const) reference to the character.
+ * @throw std::out_of_range If @a n is an invalid index.
+ *
+ * This function provides for safer data access. The parameter is
+ * first checked that it is in the range of the string. The function
+ * throws out_of_range if the check fails.
+ */
+ const_reference
+ at(size_type __n) const
+ {
+ if (__n >= this->size())
+ __throw_out_of_range_fmt(__N("basic_string::at: __n "
+ "(which is %zu) >= this->size() "
+ "(which is %zu)"),
+ __n, this->size());
+ return _M_data()[__n];
+ }
+
+ /**
+ * @brief Provides access to the data contained in the %string.
+ * @param __n The index of the character to access.
+ * @return Read/write reference to the character.
+ * @throw std::out_of_range If @a n is an invalid index.
+ *
+ * This function provides for safer data access. The parameter is
+ * first checked that it is in the range of the string. The function
+ * throws out_of_range if the check fails. Success results in
+ * unsharing the string.
+ */
+ reference
+ at(size_type __n)
+ {
+ if (__n >= size())
+ __throw_out_of_range_fmt(__N("basic_string::at: __n "
+ "(which is %zu) >= this->size() "
+ "(which is %zu)"),
+ __n, this->size());
+ _M_leak();
+ return _M_data()[__n];
+ }
+
+#if __cplusplus >= 201103L
+ /**
+ * Returns a read/write reference to the data at the first
+ * element of the %string.
+ */
+ reference
+ front()
+ {
+ __glibcxx_assert(!empty());
+ return operator[](0);
+ }
+
+ /**
+ * Returns a read-only (constant) reference to the data at the first
+ * element of the %string.
+ */
+ const_reference
+ front() const noexcept
+ {
+ __glibcxx_assert(!empty());
+ return operator[](0);
+ }
+
+ /**
+ * Returns a read/write reference to the data at the last
+ * element of the %string.
+ */
+ reference
+ back()
+ {
+ __glibcxx_assert(!empty());
+ return operator[](this->size() - 1);
+ }
+
+ /**
+ * Returns a read-only (constant) reference to the data at the
+ * last element of the %string.
+ */
+ const_reference
+ back() const noexcept
+ {
+ __glibcxx_assert(!empty());
+ return operator[](this->size() - 1);
+ }
+#endif
+
+ // Modifiers:
+ /**
+ * @brief Append a string to this string.
+ * @param __str The string to append.
+ * @return Reference to this string.
+ */
+ basic_string&
+ operator+=(const basic_string& __str)
+ { return this->append(__str); }
+
+ /**
+ * @brief Append a C string.
+ * @param __s The C string to append.
+ * @return Reference to this string.
+ */
+ basic_string&
+ operator+=(const _CharT* __s)
+ { return this->append(__s); }
+
+ /**
+ * @brief Append a character.
+ * @param __c The character to append.
+ * @return Reference to this string.
+ */
+ basic_string&
+ operator+=(_CharT __c)
+ {
+ this->push_back(__c);
+ return *this;
+ }
+
+#if __cplusplus >= 201103L
+ /**
+ * @brief Append an initializer_list of characters.
+ * @param __l The initializer_list of characters to be appended.
+ * @return Reference to this string.
+ */
+ basic_string&
+ operator+=(initializer_list<_CharT> __l)
+ { return this->append(__l.begin(), __l.size()); }
+#endif // C++11
+
+#if __cplusplus >= 201703L
+ /**
+ * @brief Append a string_view.
+ * @param __svt The object convertible to string_view to be appended.
+ * @return Reference to this string.
+ */
+ template<typename _Tp>
+ _If_sv<_Tp, basic_string&>
+ operator+=(const _Tp& __svt)
+ { return this->append(__svt); }
+#endif // C++17
+
+ /**
+ * @brief Append a string to this string.
+ * @param __str The string to append.
+ * @return Reference to this string.
+ */
+ basic_string&
+ append(const basic_string& __str);
+
+ /**
+ * @brief Append a substring.
+ * @param __str The string to append.
+ * @param __pos Index of the first character of str to append.
+ * @param __n The number of characters to append.
+ * @return Reference to this string.
+ * @throw std::out_of_range if @a __pos is not a valid index.
+ *
+ * This function appends @a __n characters from @a __str
+ * starting at @a __pos to this string. If @a __n is is larger
+ * than the number of available characters in @a __str, the
+ * remainder of @a __str is appended.
+ */
+ basic_string&
+ append(const basic_string& __str, size_type __pos, size_type __n = npos);
+
+ /**
+ * @brief Append a C substring.
+ * @param __s The C string to append.
+ * @param __n The number of characters to append.
+ * @return Reference to this string.
+ */
+ basic_string&
+ append(const _CharT* __s, size_type __n);
+
+ /**
+ * @brief Append a C string.
+ * @param __s The C string to append.
+ * @return Reference to this string.
+ */
+ basic_string&
+ append(const _CharT* __s)
+ {
+ __glibcxx_requires_string(__s);
+ return this->append(__s, traits_type::length(__s));
+ }
+
+ /**
+ * @brief Append multiple characters.
+ * @param __n The number of characters to append.
+ * @param __c The character to use.
+ * @return Reference to this string.
+ *
+ * Appends __n copies of __c to this string.
+ */
+ basic_string&
+ append(size_type __n, _CharT __c);
+
+#if __cplusplus >= 201103L
+ /**
+ * @brief Append an initializer_list of characters.
+ * @param __l The initializer_list of characters to append.
+ * @return Reference to this string.
+ */
+ basic_string&
+ append(initializer_list<_CharT> __l)
+ { return this->append(__l.begin(), __l.size()); }
+#endif // C++11
+
+ /**
+ * @brief Append a range of characters.
+ * @param __first Iterator referencing the first character to append.
+ * @param __last Iterator marking the end of the range.
+ * @return Reference to this string.
+ *
+ * Appends characters in the range [__first,__last) to this string.
+ */
+ template<class _InputIterator>
+ basic_string&
+ append(_InputIterator __first, _InputIterator __last)
+ { return this->replace(_M_iend(), _M_iend(), __first, __last); }
+
+#if __cplusplus >= 201703L
+ /**
+ * @brief Append a string_view.
+ * @param __svt The object convertible to string_view to be appended.
+ * @return Reference to this string.
+ */
+ template<typename _Tp>
+ _If_sv<_Tp, basic_string&>
+ append(const _Tp& __svt)
+ {
+ __sv_type __sv = __svt;
+ return this->append(__sv.data(), __sv.size());
+ }
+
+ /**
+ * @brief Append a range of characters from a string_view.
+ * @param __svt The object convertible to string_view to be appended
+ * from.
+ * @param __pos The position in the string_view to append from.
+ * @param __n The number of characters to append from the string_view.
+ * @return Reference to this string.
+ */
+ template<typename _Tp>
+ _If_sv<_Tp, basic_string&>
+ append(const _Tp& __svt, size_type __pos, size_type __n = npos)
+ {
+ __sv_type __sv = __svt;
+ return append(__sv.data()
+ + std::__sv_check(__sv.size(), __pos, "basic_string::append"),
+ std::__sv_limit(__sv.size(), __pos, __n));
+ }
+#endif // C++17
+
+ /**
+ * @brief Append a single character.
+ * @param __c Character to append.
+ */
+ void
+ push_back(_CharT __c)
+ {
+ const size_type __len = 1 + this->size();
+ if (__len > this->capacity() || _M_rep()->_M_is_shared())
+ this->reserve(__len);
+ traits_type::assign(_M_data()[this->size()], __c);
+ _M_rep()->_M_set_length_and_sharable(__len);
+ }
+
+ /**
+ * @brief Set value to contents of another string.
+ * @param __str Source string to use.
+ * @return Reference to this string.
+ */
+ basic_string&
+ assign(const basic_string& __str);
+
+#if __cplusplus >= 201103L
+ /**
+ * @brief Set value to contents of another string.
+ * @param __str Source string to use.
+ * @return Reference to this string.
+ *
+ * This function sets this string to the exact contents of @a __str.
+ * @a __str is a valid, but unspecified string.
+ */
+ basic_string&
+ assign(basic_string&& __str)
+ noexcept(allocator_traits<_Alloc>::is_always_equal::value)
+ {
+ this->swap(__str);
+ return *this;
+ }
+#endif // C++11
+
+ /**
+ * @brief Set value to a substring of a string.
+ * @param __str The string to use.
+ * @param __pos Index of the first character of str.
+ * @param __n Number of characters to use.
+ * @return Reference to this string.
+ * @throw std::out_of_range if @a pos is not a valid index.
+ *
+ * This function sets this string to the substring of @a __str
+ * consisting of @a __n characters at @a __pos. If @a __n is
+ * is larger than the number of available characters in @a
+ * __str, the remainder of @a __str is used.
+ */
+ basic_string&
+ assign(const basic_string& __str, size_type __pos, size_type __n = npos)
+ { return this->assign(__str._M_data()
+ + __str._M_check(__pos, "basic_string::assign"),
+ __str._M_limit(__pos, __n)); }
+
+ /**
+ * @brief Set value to a C substring.
+ * @param __s The C string to use.
+ * @param __n Number of characters to use.
+ * @return Reference to this string.
+ *
+ * This function sets the value of this string to the first @a __n
+ * characters of @a __s. If @a __n is is larger than the number of
+ * available characters in @a __s, the remainder of @a __s is used.
+ */
+ basic_string&
+ assign(const _CharT* __s, size_type __n);
+
+ /**
+ * @brief Set value to contents of a C string.
+ * @param __s The C string to use.
+ * @return Reference to this string.
+ *
+ * This function sets the value of this string to the value of @a __s.
+ * The data is copied, so there is no dependence on @a __s once the
+ * function returns.
+ */
+ basic_string&
+ assign(const _CharT* __s)
+ {
+ __glibcxx_requires_string(__s);
+ return this->assign(__s, traits_type::length(__s));
+ }
+
+ /**
+ * @brief Set value to multiple characters.
+ * @param __n Length of the resulting string.
+ * @param __c The character to use.
+ * @return Reference to this string.
+ *
+ * This function sets the value of this string to @a __n copies of
+ * character @a __c.
+ */
+ basic_string&
+ assign(size_type __n, _CharT __c)
+ { return _M_replace_aux(size_type(0), this->size(), __n, __c); }
+
+ /**
+ * @brief Set value to a range of characters.
+ * @param __first Iterator referencing the first character to append.
+ * @param __last Iterator marking the end of the range.
+ * @return Reference to this string.
+ *
+ * Sets value of string to characters in the range [__first,__last).
+ */
+ template<class _InputIterator>
+ basic_string&
+ assign(_InputIterator __first, _InputIterator __last)
+ { return this->replace(_M_ibegin(), _M_iend(), __first, __last); }
+
+#if __cplusplus >= 201103L
+ /**
+ * @brief Set value to an initializer_list of characters.
+ * @param __l The initializer_list of characters to assign.
+ * @return Reference to this string.
+ */
+ basic_string&
+ assign(initializer_list<_CharT> __l)
+ { return this->assign(__l.begin(), __l.size()); }
+#endif // C++11
+
+#if __cplusplus >= 201703L
+ /**
+ * @brief Set value from a string_view.
+ * @param __svt The source object convertible to string_view.
+ * @return Reference to this string.
+ */
+ template<typename _Tp>
+ _If_sv<_Tp, basic_string&>
+ assign(const _Tp& __svt)
+ {
+ __sv_type __sv = __svt;
+ return this->assign(__sv.data(), __sv.size());
+ }
+
+ /**
+ * @brief Set value from a range of characters in a string_view.
+ * @param __svt The source object convertible to string_view.
+ * @param __pos The position in the string_view to assign from.
+ * @param __n The number of characters to assign.
+ * @return Reference to this string.
+ */
+ template<typename _Tp>
+ _If_sv<_Tp, basic_string&>
+ assign(const _Tp& __svt, size_type __pos, size_type __n = npos)
+ {
+ __sv_type __sv = __svt;
+ return assign(__sv.data()
+ + std::__sv_check(__sv.size(), __pos, "basic_string::assign"),
+ std::__sv_limit(__sv.size(), __pos, __n));
+ }
+#endif // C++17
+
+ /**
+ * @brief Insert multiple characters.
+ * @param __p Iterator referencing location in string to insert at.
+ * @param __n Number of characters to insert
+ * @param __c The character to insert.
+ * @throw std::length_error If new length exceeds @c max_size().
+ *
+ * Inserts @a __n copies of character @a __c starting at the
+ * position referenced by iterator @a __p. If adding
+ * characters causes the length to exceed max_size(),
+ * length_error is thrown. The value of the string doesn't
+ * change if an error is thrown.
+ */
+ void
+ insert(iterator __p, size_type __n, _CharT __c)
+ { this->replace(__p, __p, __n, __c); }
+
+ /**
+ * @brief Insert a range of characters.
+ * @param __p Iterator referencing location in string to insert at.
+ * @param __beg Start of range.
+ * @param __end End of range.
+ * @throw std::length_error If new length exceeds @c max_size().
+ *
+ * Inserts characters in range [__beg,__end). If adding
+ * characters causes the length to exceed max_size(),
+ * length_error is thrown. The value of the string doesn't
+ * change if an error is thrown.
+ */
+ template<class _InputIterator>
+ void
+ insert(iterator __p, _InputIterator __beg, _InputIterator __end)
+ { this->replace(__p, __p, __beg, __end); }
+
+#if __cplusplus >= 201103L
+ /**
+ * @brief Insert an initializer_list of characters.
+ * @param __p Iterator referencing location in string to insert at.
+ * @param __l The initializer_list of characters to insert.
+ * @throw std::length_error If new length exceeds @c max_size().
+ */
+ void
+ insert(iterator __p, initializer_list<_CharT> __l)
+ {
+ _GLIBCXX_DEBUG_PEDASSERT(__p >= _M_ibegin() && __p <= _M_iend());
+ this->insert(__p - _M_ibegin(), __l.begin(), __l.size());
+ }
+#endif // C++11
+
+ /**
+ * @brief Insert value of a string.
+ * @param __pos1 Position in string to insert at.
+ * @param __str The string to insert.
+ * @return Reference to this string.
+ * @throw std::length_error If new length exceeds @c max_size().
+ *
+ * Inserts value of @a __str starting at @a __pos1. If adding
+ * characters causes the length to exceed max_size(),
+ * length_error is thrown. The value of the string doesn't
+ * change if an error is thrown.
+ */
+ basic_string&
+ insert(size_type __pos1, const basic_string& __str)
+ { return this->insert(__pos1, __str, size_type(0), __str.size()); }
+
+ /**
+ * @brief Insert a substring.
+ * @param __pos1 Position in string to insert at.
+ * @param __str The string to insert.
+ * @param __pos2 Start of characters in str to insert.
+ * @param __n Number of characters to insert.
+ * @return Reference to this string.
+ * @throw std::length_error If new length exceeds @c max_size().
+ * @throw std::out_of_range If @a pos1 > size() or
+ * @a __pos2 > @a str.size().
+ *
+ * Starting at @a pos1, insert @a __n character of @a __str
+ * beginning with @a __pos2. If adding characters causes the
+ * length to exceed max_size(), length_error is thrown. If @a
+ * __pos1 is beyond the end of this string or @a __pos2 is
+ * beyond the end of @a __str, out_of_range is thrown. The
+ * value of the string doesn't change if an error is thrown.
+ */
+ basic_string&
+ insert(size_type __pos1, const basic_string& __str,
+ size_type __pos2, size_type __n = npos)
+ { return this->insert(__pos1, __str._M_data()
+ + __str._M_check(__pos2, "basic_string::insert"),
+ __str._M_limit(__pos2, __n)); }
+
+ /**
+ * @brief Insert a C substring.
+ * @param __pos Position in string to insert at.
+ * @param __s The C string to insert.
+ * @param __n The number of characters to insert.
+ * @return Reference to this string.
+ * @throw std::length_error If new length exceeds @c max_size().
+ * @throw std::out_of_range If @a __pos is beyond the end of this
+ * string.
+ *
+ * Inserts the first @a __n characters of @a __s starting at @a
+ * __pos. If adding characters causes the length to exceed
+ * max_size(), length_error is thrown. If @a __pos is beyond
+ * end(), out_of_range is thrown. The value of the string
+ * doesn't change if an error is thrown.
+ */
+ basic_string&
+ insert(size_type __pos, const _CharT* __s, size_type __n);
+
+ /**
+ * @brief Insert a C string.
+ * @param __pos Position in string to insert at.
+ * @param __s The C string to insert.
+ * @return Reference to this string.
+ * @throw std::length_error If new length exceeds @c max_size().
+ * @throw std::out_of_range If @a pos is beyond the end of this
+ * string.
+ *
+ * Inserts the first @a n characters of @a __s starting at @a __pos. If
+ * adding characters causes the length to exceed max_size(),
+ * length_error is thrown. If @a __pos is beyond end(), out_of_range is
+ * thrown. The value of the string doesn't change if an error is
+ * thrown.
+ */
+ basic_string&
+ insert(size_type __pos, const _CharT* __s)
+ {
+ __glibcxx_requires_string(__s);
+ return this->insert(__pos, __s, traits_type::length(__s));
+ }
+
+ /**
+ * @brief Insert multiple characters.
+ * @param __pos Index in string to insert at.
+ * @param __n Number of characters to insert
+ * @param __c The character to insert.
+ * @return Reference to this string.
+ * @throw std::length_error If new length exceeds @c max_size().
+ * @throw std::out_of_range If @a __pos is beyond the end of this
+ * string.
+ *
+ * Inserts @a __n copies of character @a __c starting at index
+ * @a __pos. If adding characters causes the length to exceed
+ * max_size(), length_error is thrown. If @a __pos > length(),
+ * out_of_range is thrown. The value of the string doesn't
+ * change if an error is thrown.
+ */
+ basic_string&
+ insert(size_type __pos, size_type __n, _CharT __c)
+ { return _M_replace_aux(_M_check(__pos, "basic_string::insert"),
+ size_type(0), __n, __c); }
+
+ /**
+ * @brief Insert one character.
+ * @param __p Iterator referencing position in string to insert at.
+ * @param __c The character to insert.
+ * @return Iterator referencing newly inserted char.
+ * @throw std::length_error If new length exceeds @c max_size().
+ *
+ * Inserts character @a __c at position referenced by @a __p.
+ * If adding character causes the length to exceed max_size(),
+ * length_error is thrown. If @a __p is beyond end of string,
+ * out_of_range is thrown. The value of the string doesn't
+ * change if an error is thrown.
+ */
+ iterator
+ insert(iterator __p, _CharT __c)
+ {
+ _GLIBCXX_DEBUG_PEDASSERT(__p >= _M_ibegin() && __p <= _M_iend());
+ const size_type __pos = __p - _M_ibegin();
+ _M_replace_aux(__pos, size_type(0), size_type(1), __c);
+ _M_rep()->_M_set_leaked();
+ return iterator(_M_data() + __pos);
+ }
+
+#if __cplusplus >= 201703L
+ /**
+ * @brief Insert a string_view.
+ * @param __pos Position in string to insert at.
+ * @param __svt The object convertible to string_view to insert.
+ * @return Reference to this string.
+ */
+ template<typename _Tp>
+ _If_sv<_Tp, basic_string&>
+ insert(size_type __pos, const _Tp& __svt)
+ {
+ __sv_type __sv = __svt;
+ return this->insert(__pos, __sv.data(), __sv.size());
+ }
+
+ /**
+ * @brief Insert a string_view.
+ * @param __pos1 Position in string to insert at.
+ * @param __svt The object convertible to string_view to insert from.
+ * @param __pos2 Position in string_view to insert from.
+ * @param __n The number of characters to insert.
+ * @return Reference to this string.
+ */
+ template<typename _Tp>
+ _If_sv<_Tp, basic_string&>
+ insert(size_type __pos1, const _Tp& __svt,
+ size_type __pos2, size_type __n = npos)
+ {
+ __sv_type __sv = __svt;
+ return this->replace(__pos1, size_type(0), __sv.data()
+ + std::__sv_check(__sv.size(), __pos2, "basic_string::insert"),
+ std::__sv_limit(__sv.size(), __pos2, __n));
+ }
+#endif // C++17
+
+ /**
+ * @brief Remove characters.
+ * @param __pos Index of first character to remove (default 0).
+ * @param __n Number of characters to remove (default remainder).
+ * @return Reference to this string.
+ * @throw std::out_of_range If @a pos is beyond the end of this
+ * string.
+ *
+ * Removes @a __n characters from this string starting at @a
+ * __pos. The length of the string is reduced by @a __n. If
+ * there are < @a __n characters to remove, the remainder of
+ * the string is truncated. If @a __p is beyond end of string,
+ * out_of_range is thrown. The value of the string doesn't
+ * change if an error is thrown.
+ */
+ basic_string&
+ erase(size_type __pos = 0, size_type __n = npos)
+ {
+ _M_mutate(_M_check(__pos, "basic_string::erase"),
+ _M_limit(__pos, __n), size_type(0));
+ return *this;
+ }
+
+ /**
+ * @brief Remove one character.
+ * @param __position Iterator referencing the character to remove.
+ * @return iterator referencing same location after removal.
+ *
+ * Removes the character at @a __position from this string. The value
+ * of the string doesn't change if an error is thrown.
+ */
+ iterator
+ erase(iterator __position)
+ {
+ _GLIBCXX_DEBUG_PEDASSERT(__position >= _M_ibegin()
+ && __position < _M_iend());
+ const size_type __pos = __position - _M_ibegin();
+ _M_mutate(__pos, size_type(1), size_type(0));
+ _M_rep()->_M_set_leaked();
+ return iterator(_M_data() + __pos);
+ }
+
+ /**
+ * @brief Remove a range of characters.
+ * @param __first Iterator referencing the first character to remove.
+ * @param __last Iterator referencing the end of the range.
+ * @return Iterator referencing location of first after removal.
+ *
+ * Removes the characters in the range [first,last) from this string.
+ * The value of the string doesn't change if an error is thrown.
+ */
+ iterator
+ erase(iterator __first, iterator __last);
+
+#if __cplusplus >= 201103L
+ /**
+ * @brief Remove the last character.
+ *
+ * The string must be non-empty.
+ */
+ void
+ pop_back() // FIXME C++11: should be noexcept.
+ {
+ __glibcxx_assert(!empty());
+ erase(size() - 1, 1);
+ }
+#endif // C++11
+
+ /**
+ * @brief Replace characters with value from another string.
+ * @param __pos Index of first character to replace.
+ * @param __n Number of characters to be replaced.
+ * @param __str String to insert.
+ * @return Reference to this string.
+ * @throw std::out_of_range If @a pos is beyond the end of this
+ * string.
+ * @throw std::length_error If new length exceeds @c max_size().
+ *
+ * Removes the characters in the range [__pos,__pos+__n) from
+ * this string. In place, the value of @a __str is inserted.
+ * If @a __pos is beyond end of string, out_of_range is thrown.
+ * If the length of the result exceeds max_size(), length_error
+ * is thrown. The value of the string doesn't change if an
+ * error is thrown.
+ */
+ basic_string&
+ replace(size_type __pos, size_type __n, const basic_string& __str)
+ { return this->replace(__pos, __n, __str._M_data(), __str.size()); }
+
+ /**
+ * @brief Replace characters with value from another string.
+ * @param __pos1 Index of first character to replace.
+ * @param __n1 Number of characters to be replaced.
+ * @param __str String to insert.
+ * @param __pos2 Index of first character of str to use.
+ * @param __n2 Number of characters from str to use.
+ * @return Reference to this string.
+ * @throw std::out_of_range If @a __pos1 > size() or @a __pos2 >
+ * __str.size().
+ * @throw std::length_error If new length exceeds @c max_size().
+ *
+ * Removes the characters in the range [__pos1,__pos1 + n) from this
+ * string. In place, the value of @a __str is inserted. If @a __pos is
+ * beyond end of string, out_of_range is thrown. If the length of the
+ * result exceeds max_size(), length_error is thrown. The value of the
+ * string doesn't change if an error is thrown.
+ */
+ basic_string&
+ replace(size_type __pos1, size_type __n1, const basic_string& __str,
+ size_type __pos2, size_type __n2 = npos)
+ { return this->replace(__pos1, __n1, __str._M_data()
+ + __str._M_check(__pos2, "basic_string::replace"),
+ __str._M_limit(__pos2, __n2)); }
+
+ /**
+ * @brief Replace characters with value of a C substring.
+ * @param __pos Index of first character to replace.
+ * @param __n1 Number of characters to be replaced.
+ * @param __s C string to insert.
+ * @param __n2 Number of characters from @a s to use.
+ * @return Reference to this string.
+ * @throw std::out_of_range If @a pos1 > size().
+ * @throw std::length_error If new length exceeds @c max_size().
+ *
+ * Removes the characters in the range [__pos,__pos + __n1)
+ * from this string. In place, the first @a __n2 characters of
+ * @a __s are inserted, or all of @a __s if @a __n2 is too large. If
+ * @a __pos is beyond end of string, out_of_range is thrown. If
+ * the length of result exceeds max_size(), length_error is
+ * thrown. The value of the string doesn't change if an error
+ * is thrown.
+ */
+ basic_string&
+ replace(size_type __pos, size_type __n1, const _CharT* __s,
+ size_type __n2);
+
+ /**
+ * @brief Replace characters with value of a C string.
+ * @param __pos Index of first character to replace.
+ * @param __n1 Number of characters to be replaced.
+ * @param __s C string to insert.
+ * @return Reference to this string.
+ * @throw std::out_of_range If @a pos > size().
+ * @throw std::length_error If new length exceeds @c max_size().
+ *
+ * Removes the characters in the range [__pos,__pos + __n1)
+ * from this string. In place, the characters of @a __s are
+ * inserted. If @a __pos is beyond end of string, out_of_range
+ * is thrown. If the length of result exceeds max_size(),
+ * length_error is thrown. The value of the string doesn't
+ * change if an error is thrown.
+ */
+ basic_string&
+ replace(size_type __pos, size_type __n1, const _CharT* __s)
+ {
+ __glibcxx_requires_string(__s);
+ return this->replace(__pos, __n1, __s, traits_type::length(__s));
+ }
+
+ /**
+ * @brief Replace characters with multiple characters.
+ * @param __pos Index of first character to replace.
+ * @param __n1 Number of characters to be replaced.
+ * @param __n2 Number of characters to insert.
+ * @param __c Character to insert.
+ * @return Reference to this string.
+ * @throw std::out_of_range If @a __pos > size().
+ * @throw std::length_error If new length exceeds @c max_size().
+ *
+ * Removes the characters in the range [pos,pos + n1) from this
+ * string. In place, @a __n2 copies of @a __c are inserted.
+ * If @a __pos is beyond end of string, out_of_range is thrown.
+ * If the length of result exceeds max_size(), length_error is
+ * thrown. The value of the string doesn't change if an error
+ * is thrown.
+ */
+ basic_string&
+ replace(size_type __pos, size_type __n1, size_type __n2, _CharT __c)
+ { return _M_replace_aux(_M_check(__pos, "basic_string::replace"),
+ _M_limit(__pos, __n1), __n2, __c); }
+
+ /**
+ * @brief Replace range of characters with string.
+ * @param __i1 Iterator referencing start of range to replace.
+ * @param __i2 Iterator referencing end of range to replace.
+ * @param __str String value to insert.
+ * @return Reference to this string.
+ * @throw std::length_error If new length exceeds @c max_size().
+ *
+ * Removes the characters in the range [__i1,__i2). In place,
+ * the value of @a __str is inserted. If the length of result
+ * exceeds max_size(), length_error is thrown. The value of
+ * the string doesn't change if an error is thrown.
+ */
+ basic_string&
+ replace(iterator __i1, iterator __i2, const basic_string& __str)
+ { return this->replace(__i1, __i2, __str._M_data(), __str.size()); }
+
+ /**
+ * @brief Replace range of characters with C substring.
+ * @param __i1 Iterator referencing start of range to replace.
+ * @param __i2 Iterator referencing end of range to replace.
+ * @param __s C string value to insert.
+ * @param __n Number of characters from s to insert.
+ * @return Reference to this string.
+ * @throw std::length_error If new length exceeds @c max_size().
+ *
+ * Removes the characters in the range [__i1,__i2). In place,
+ * the first @a __n characters of @a __s are inserted. If the
+ * length of result exceeds max_size(), length_error is thrown.
+ * The value of the string doesn't change if an error is
+ * thrown.
+ */
+ basic_string&
+ replace(iterator __i1, iterator __i2, const _CharT* __s, size_type __n)
+ {
+ _GLIBCXX_DEBUG_PEDASSERT(_M_ibegin() <= __i1 && __i1 <= __i2
+ && __i2 <= _M_iend());
+ return this->replace(__i1 - _M_ibegin(), __i2 - __i1, __s, __n);
+ }
+
+ /**
+ * @brief Replace range of characters with C string.
+ * @param __i1 Iterator referencing start of range to replace.
+ * @param __i2 Iterator referencing end of range to replace.
+ * @param __s C string value to insert.
+ * @return Reference to this string.
+ * @throw std::length_error If new length exceeds @c max_size().
+ *
+ * Removes the characters in the range [__i1,__i2). In place,
+ * the characters of @a __s are inserted. If the length of
+ * result exceeds max_size(), length_error is thrown. The
+ * value of the string doesn't change if an error is thrown.
+ */
+ basic_string&
+ replace(iterator __i1, iterator __i2, const _CharT* __s)
+ {
+ __glibcxx_requires_string(__s);
+ return this->replace(__i1, __i2, __s, traits_type::length(__s));
+ }
+
+ /**
+ * @brief Replace range of characters with multiple characters
+ * @param __i1 Iterator referencing start of range to replace.
+ * @param __i2 Iterator referencing end of range to replace.
+ * @param __n Number of characters to insert.
+ * @param __c Character to insert.
+ * @return Reference to this string.
+ * @throw std::length_error If new length exceeds @c max_size().
+ *
+ * Removes the characters in the range [__i1,__i2). In place,
+ * @a __n copies of @a __c are inserted. If the length of
+ * result exceeds max_size(), length_error is thrown. The
+ * value of the string doesn't change if an error is thrown.
+ */
+ basic_string&
+ replace(iterator __i1, iterator __i2, size_type __n, _CharT __c)
+ {
+ _GLIBCXX_DEBUG_PEDASSERT(_M_ibegin() <= __i1 && __i1 <= __i2
+ && __i2 <= _M_iend());
+ return _M_replace_aux(__i1 - _M_ibegin(), __i2 - __i1, __n, __c);
+ }
+
+ /**
+ * @brief Replace range of characters with range.
+ * @param __i1 Iterator referencing start of range to replace.
+ * @param __i2 Iterator referencing end of range to replace.
+ * @param __k1 Iterator referencing start of range to insert.
+ * @param __k2 Iterator referencing end of range to insert.
+ * @return Reference to this string.
+ * @throw std::length_error If new length exceeds @c max_size().
+ *
+ * Removes the characters in the range [__i1,__i2). In place,
+ * characters in the range [__k1,__k2) are inserted. If the
+ * length of result exceeds max_size(), length_error is thrown.
+ * The value of the string doesn't change if an error is
+ * thrown.
+ */
+ template<class _InputIterator>
+ basic_string&
+ replace(iterator __i1, iterator __i2,
+ _InputIterator __k1, _InputIterator __k2)
+ {
+ _GLIBCXX_DEBUG_PEDASSERT(_M_ibegin() <= __i1 && __i1 <= __i2
+ && __i2 <= _M_iend());
+ __glibcxx_requires_valid_range(__k1, __k2);
+ typedef typename std::__is_integer<_InputIterator>::__type _Integral;
+ return _M_replace_dispatch(__i1, __i2, __k1, __k2, _Integral());
+ }
+
+ // Specializations for the common case of pointer and iterator:
+ // useful to avoid the overhead of temporary buffering in _M_replace.
+ basic_string&
+ replace(iterator __i1, iterator __i2, _CharT* __k1, _CharT* __k2)
+ {
+ _GLIBCXX_DEBUG_PEDASSERT(_M_ibegin() <= __i1 && __i1 <= __i2
+ && __i2 <= _M_iend());
+ __glibcxx_requires_valid_range(__k1, __k2);
+ return this->replace(__i1 - _M_ibegin(), __i2 - __i1,
+ __k1, __k2 - __k1);
+ }
+
+ basic_string&
+ replace(iterator __i1, iterator __i2,
+ const _CharT* __k1, const _CharT* __k2)
+ {
+ _GLIBCXX_DEBUG_PEDASSERT(_M_ibegin() <= __i1 && __i1 <= __i2
+ && __i2 <= _M_iend());
+ __glibcxx_requires_valid_range(__k1, __k2);
+ return this->replace(__i1 - _M_ibegin(), __i2 - __i1,
+ __k1, __k2 - __k1);
+ }
+
+ basic_string&
+ replace(iterator __i1, iterator __i2, iterator __k1, iterator __k2)
+ {
+ _GLIBCXX_DEBUG_PEDASSERT(_M_ibegin() <= __i1 && __i1 <= __i2
+ && __i2 <= _M_iend());
+ __glibcxx_requires_valid_range(__k1, __k2);
+ return this->replace(__i1 - _M_ibegin(), __i2 - __i1,
+ __k1.base(), __k2 - __k1);
+ }
+
+ basic_string&
+ replace(iterator __i1, iterator __i2,
+ const_iterator __k1, const_iterator __k2)
+ {
+ _GLIBCXX_DEBUG_PEDASSERT(_M_ibegin() <= __i1 && __i1 <= __i2
+ && __i2 <= _M_iend());
+ __glibcxx_requires_valid_range(__k1, __k2);
+ return this->replace(__i1 - _M_ibegin(), __i2 - __i1,
+ __k1.base(), __k2 - __k1);
+ }
+
+#if __cplusplus >= 201103L
+ /**
+ * @brief Replace range of characters with initializer_list.
+ * @param __i1 Iterator referencing start of range to replace.
+ * @param __i2 Iterator referencing end of range to replace.
+ * @param __l The initializer_list of characters to insert.
+ * @return Reference to this string.
+ * @throw std::length_error If new length exceeds @c max_size().
+ *
+ * Removes the characters in the range [__i1,__i2). In place,
+ * characters in the range [__k1,__k2) are inserted. If the
+ * length of result exceeds max_size(), length_error is thrown.
+ * The value of the string doesn't change if an error is
+ * thrown.
+ */
+ basic_string& replace(iterator __i1, iterator __i2,
+ initializer_list<_CharT> __l)
+ { return this->replace(__i1, __i2, __l.begin(), __l.end()); }
+#endif // C++11
+
+#if __cplusplus >= 201703L
+ /**
+ * @brief Replace range of characters with string_view.
+ * @param __pos The position to replace at.
+ * @param __n The number of characters to replace.
+ * @param __svt The object convertible to string_view to insert.
+ * @return Reference to this string.
+ */
+ template<typename _Tp>
+ _If_sv<_Tp, basic_string&>
+ replace(size_type __pos, size_type __n, const _Tp& __svt)
+ {
+ __sv_type __sv = __svt;
+ return this->replace(__pos, __n, __sv.data(), __sv.size());
+ }
+
+ /**
+ * @brief Replace range of characters with string_view.
+ * @param __pos1 The position to replace at.
+ * @param __n1 The number of characters to replace.
+ * @param __svt The object convertible to string_view to insert from.
+ * @param __pos2 The position in the string_view to insert from.
+ * @param __n2 The number of characters to insert.
+ * @return Reference to this string.
+ */
+ template<typename _Tp>
+ _If_sv<_Tp, basic_string&>
+ replace(size_type __pos1, size_type __n1, const _Tp& __svt,
+ size_type __pos2, size_type __n2 = npos)
+ {
+ __sv_type __sv = __svt;
+ return this->replace(__pos1, __n1,
+ __sv.data()
+ + std::__sv_check(__sv.size(), __pos2, "basic_string::replace"),
+ std::__sv_limit(__sv.size(), __pos2, __n2));
+ }
+
+ /**
+ * @brief Replace range of characters with string_view.
+ * @param __i1 An iterator referencing the start position
+ to replace at.
+ * @param __i2 An iterator referencing the end position
+ for the replace.
+ * @param __svt The object convertible to string_view to insert from.
+ * @return Reference to this string.
+ */
+ template<typename _Tp>
+ _If_sv<_Tp, basic_string&>
+ replace(const_iterator __i1, const_iterator __i2, const _Tp& __svt)
+ {
+ __sv_type __sv = __svt;
+ return this->replace(__i1 - begin(), __i2 - __i1, __sv);
+ }
+#endif // C++17
+
+ private:
+ template<class _Integer>
+ basic_string&
+ _M_replace_dispatch(iterator __i1, iterator __i2, _Integer __n,
+ _Integer __val, __true_type)
+ { return _M_replace_aux(__i1 - _M_ibegin(), __i2 - __i1, __n, __val); }
+
+ template<class _InputIterator>
+ basic_string&
+ _M_replace_dispatch(iterator __i1, iterator __i2, _InputIterator __k1,
+ _InputIterator __k2, __false_type);
+
+ basic_string&
+ _M_replace_aux(size_type __pos1, size_type __n1, size_type __n2,
+ _CharT __c);
+
+ basic_string&
+ _M_replace_safe(size_type __pos1, size_type __n1, const _CharT* __s,
+ size_type __n2);
+
+ // _S_construct_aux is used to implement the 21.3.1 para 15 which
+ // requires special behaviour if _InIter is an integral type
+ template<class _InIterator>
+ static _CharT*
+ _S_construct_aux(_InIterator __beg, _InIterator __end,
+ const _Alloc& __a, __false_type)
+ {
+ typedef typename iterator_traits<_InIterator>::iterator_category _Tag;
+ return _S_construct(__beg, __end, __a, _Tag());
+ }
+
+ // _GLIBCXX_RESOLVE_LIB_DEFECTS
+ // 438. Ambiguity in the "do the right thing" clause
+ template<class _Integer>
+ static _CharT*
+ _S_construct_aux(_Integer __beg, _Integer __end,
+ const _Alloc& __a, __true_type)
+ { return _S_construct_aux_2(static_cast<size_type>(__beg),
+ __end, __a); }
+
+ static _CharT*
+ _S_construct_aux_2(size_type __req, _CharT __c, const _Alloc& __a)
+ { return _S_construct(__req, __c, __a); }
+
+ template<class _InIterator>
+ static _CharT*
+ _S_construct(_InIterator __beg, _InIterator __end, const _Alloc& __a)
+ {
+ typedef typename std::__is_integer<_InIterator>::__type _Integral;
+ return _S_construct_aux(__beg, __end, __a, _Integral());
+ }
+
+ // For Input Iterators, used in istreambuf_iterators, etc.
+ template<class _InIterator>
+ static _CharT*
+ _S_construct(_InIterator __beg, _InIterator __end, const _Alloc& __a,
+ input_iterator_tag);
+
+ // For forward_iterators up to random_access_iterators, used for
+ // string::iterator, _CharT*, etc.
+ template<class _FwdIterator>
+ static _CharT*
+ _S_construct(_FwdIterator __beg, _FwdIterator __end, const _Alloc& __a,
+ forward_iterator_tag);
+
+ static _CharT*
+ _S_construct(size_type __req, _CharT __c, const _Alloc& __a);
+
+ public:
+
+ /**
+ * @brief Copy substring into C string.
+ * @param __s C string to copy value into.
+ * @param __n Number of characters to copy.
+ * @param __pos Index of first character to copy.
+ * @return Number of characters actually copied
+ * @throw std::out_of_range If __pos > size().
+ *
+ * Copies up to @a __n characters starting at @a __pos into the
+ * C string @a __s. If @a __pos is %greater than size(),
+ * out_of_range is thrown.
+ */
+ size_type
+ copy(_CharT* __s, size_type __n, size_type __pos = 0) const;
+
+ /**
+ * @brief Swap contents with another string.
+ * @param __s String to swap with.
+ *
+ * Exchanges the contents of this string with that of @a __s in constant
+ * time.
+ */
+ void
+ swap(basic_string& __s)
+ _GLIBCXX_NOEXCEPT_IF(allocator_traits<_Alloc>::is_always_equal::value);
+
+ // String operations:
+ /**
+ * @brief Return const pointer to null-terminated contents.
+ *
+ * This is a handle to internal data. Do not modify or dire things may
+ * happen.
+ */
+ const _CharT*
+ c_str() const _GLIBCXX_NOEXCEPT
+ { return _M_data(); }
+
+ /**
+ * @brief Return const pointer to contents.
+ *
+ * This is a pointer to internal data. It is undefined to modify
+ * the contents through the returned pointer. To get a pointer that
+ * allows modifying the contents use @c &str[0] instead,
+ * (or in C++17 the non-const @c str.data() overload).
+ */
+ const _CharT*
+ data() const _GLIBCXX_NOEXCEPT
+ { return _M_data(); }
+
+#if __cplusplus >= 201703L
+ /**
+ * @brief Return non-const pointer to contents.
+ *
+ * This is a pointer to the character sequence held by the string.
+ * Modifying the characters in the sequence is allowed.
+ */
+ _CharT*
+ data() noexcept
+ {
+ _M_leak();
+ return _M_data();
+ }
+#endif
+
+ /**
+ * @brief Return copy of allocator used to construct this string.
+ */
+ allocator_type
+ get_allocator() const _GLIBCXX_NOEXCEPT
+ { return _M_dataplus; }
+
+ /**
+ * @brief Find position of a C substring.
+ * @param __s C string to locate.
+ * @param __pos Index of character to search from.
+ * @param __n Number of characters from @a s to search for.
+ * @return Index of start of first occurrence.
+ *
+ * Starting from @a __pos, searches forward for the first @a
+ * __n characters in @a __s within this string. If found,
+ * returns the index where it begins. If not found, returns
+ * npos.
+ */
+ size_type
+ find(const _CharT* __s, size_type __pos, size_type __n) const
+ _GLIBCXX_NOEXCEPT;
+
+ /**
+ * @brief Find position of a string.
+ * @param __str String to locate.
+ * @param __pos Index of character to search from (default 0).
+ * @return Index of start of first occurrence.
+ *
+ * Starting from @a __pos, searches forward for value of @a __str within
+ * this string. If found, returns the index where it begins. If not
+ * found, returns npos.
+ */
+ size_type
+ find(const basic_string& __str, size_type __pos = 0) const
+ _GLIBCXX_NOEXCEPT
+ { return this->find(__str.data(), __pos, __str.size()); }
+
+ /**
+ * @brief Find position of a C string.
+ * @param __s C string to locate.
+ * @param __pos Index of character to search from (default 0).
+ * @return Index of start of first occurrence.
+ *
+ * Starting from @a __pos, searches forward for the value of @a
+ * __s within this string. If found, returns the index where
+ * it begins. If not found, returns npos.
+ */
+ size_type
+ find(const _CharT* __s, size_type __pos = 0) const _GLIBCXX_NOEXCEPT
+ {
+ __glibcxx_requires_string(__s);
+ return this->find(__s, __pos, traits_type::length(__s));
+ }
+
+ /**
+ * @brief Find position of a character.
+ * @param __c Character to locate.
+ * @param __pos Index of character to search from (default 0).
+ * @return Index of first occurrence.
+ *
+ * Starting from @a __pos, searches forward for @a __c within
+ * this string. If found, returns the index where it was
+ * found. If not found, returns npos.
+ */
+ size_type
+ find(_CharT __c, size_type __pos = 0) const _GLIBCXX_NOEXCEPT;
+
+#if __cplusplus >= 201703L
+ /**
+ * @brief Find position of a string_view.
+ * @param __svt The object convertible to string_view to locate.
+ * @param __pos Index of character to search from (default 0).
+ * @return Index of start of first occurrence.
+ */
+ template<typename _Tp>
+ _If_sv<_Tp, size_type>
+ find(const _Tp& __svt, size_type __pos = 0) const
+ noexcept(is_same<_Tp, __sv_type>::value)
+ {
+ __sv_type __sv = __svt;
+ return this->find(__sv.data(), __pos, __sv.size());
+ }
+#endif // C++17
+
+ /**
+ * @brief Find last position of a string.
+ * @param __str String to locate.
+ * @param __pos Index of character to search back from (default end).
+ * @return Index of start of last occurrence.
+ *
+ * Starting from @a __pos, searches backward for value of @a
+ * __str within this string. If found, returns the index where
+ * it begins. If not found, returns npos.
+ */
+ size_type
+ rfind(const basic_string& __str, size_type __pos = npos) const
+ _GLIBCXX_NOEXCEPT
+ { return this->rfind(__str.data(), __pos, __str.size()); }
+
+ /**
+ * @brief Find last position of a C substring.
+ * @param __s C string to locate.
+ * @param __pos Index of character to search back from.
+ * @param __n Number of characters from s to search for.
+ * @return Index of start of last occurrence.
+ *
+ * Starting from @a __pos, searches backward for the first @a
+ * __n characters in @a __s within this string. If found,
+ * returns the index where it begins. If not found, returns
+ * npos.
+ */
+ size_type
+ rfind(const _CharT* __s, size_type __pos, size_type __n) const
+ _GLIBCXX_NOEXCEPT;
+
+ /**
+ * @brief Find last position of a C string.
+ * @param __s C string to locate.
+ * @param __pos Index of character to start search at (default end).
+ * @return Index of start of last occurrence.
+ *
+ * Starting from @a __pos, searches backward for the value of
+ * @a __s within this string. If found, returns the index
+ * where it begins. If not found, returns npos.
+ */
+ size_type
+ rfind(const _CharT* __s, size_type __pos = npos) const _GLIBCXX_NOEXCEPT
+ {
+ __glibcxx_requires_string(__s);
+ return this->rfind(__s, __pos, traits_type::length(__s));
+ }
+
+ /**
+ * @brief Find last position of a character.
+ * @param __c Character to locate.
+ * @param __pos Index of character to search back from (default end).
+ * @return Index of last occurrence.
+ *
+ * Starting from @a __pos, searches backward for @a __c within
+ * this string. If found, returns the index where it was
+ * found. If not found, returns npos.
+ */
+ size_type
+ rfind(_CharT __c, size_type __pos = npos) const _GLIBCXX_NOEXCEPT;
+
+#if __cplusplus >= 201703L
+ /**
+ * @brief Find last position of a string_view.
+ * @param __svt The object convertible to string_view to locate.
+ * @param __pos Index of character to search back from (default end).
+ * @return Index of start of last occurrence.
+ */
+ template<typename _Tp>
+ _If_sv<_Tp, size_type>
+ rfind(const _Tp& __svt, size_type __pos = npos) const
+ noexcept(is_same<_Tp, __sv_type>::value)
+ {
+ __sv_type __sv = __svt;
+ return this->rfind(__sv.data(), __pos, __sv.size());
+ }
+#endif // C++17
+
+ /**
+ * @brief Find position of a character of string.
+ * @param __str String containing characters to locate.
+ * @param __pos Index of character to search from (default 0).
+ * @return Index of first occurrence.
+ *
+ * Starting from @a __pos, searches forward for one of the
+ * characters of @a __str within this string. If found,
+ * returns the index where it was found. If not found, returns
+ * npos.
+ */
+ size_type
+ find_first_of(const basic_string& __str, size_type __pos = 0) const
+ _GLIBCXX_NOEXCEPT
+ { return this->find_first_of(__str.data(), __pos, __str.size()); }
+
+ /**
+ * @brief Find position of a character of C substring.
+ * @param __s String containing characters to locate.
+ * @param __pos Index of character to search from.
+ * @param __n Number of characters from s to search for.
+ * @return Index of first occurrence.
+ *
+ * Starting from @a __pos, searches forward for one of the
+ * first @a __n characters of @a __s within this string. If
+ * found, returns the index where it was found. If not found,
+ * returns npos.
+ */
+ size_type
+ find_first_of(const _CharT* __s, size_type __pos, size_type __n) const
+ _GLIBCXX_NOEXCEPT;
+
+ /**
+ * @brief Find position of a character of C string.
+ * @param __s String containing characters to locate.
+ * @param __pos Index of character to search from (default 0).
+ * @return Index of first occurrence.
+ *
+ * Starting from @a __pos, searches forward for one of the
+ * characters of @a __s within this string. If found, returns
+ * the index where it was found. If not found, returns npos.
+ */
+ size_type
+ find_first_of(const _CharT* __s, size_type __pos = 0) const
+ _GLIBCXX_NOEXCEPT
+ {
+ __glibcxx_requires_string(__s);
+ return this->find_first_of(__s, __pos, traits_type::length(__s));
+ }
+
+ /**
+ * @brief Find position of a character.
+ * @param __c Character to locate.
+ * @param __pos Index of character to search from (default 0).
+ * @return Index of first occurrence.
+ *
+ * Starting from @a __pos, searches forward for the character
+ * @a __c within this string. If found, returns the index
+ * where it was found. If not found, returns npos.
+ *
+ * Note: equivalent to find(__c, __pos).
+ */
+ size_type
+ find_first_of(_CharT __c, size_type __pos = 0) const _GLIBCXX_NOEXCEPT
+ { return this->find(__c, __pos); }
+
+#if __cplusplus >= 201703L
+ /**
+ * @brief Find position of a character of a string_view.
+ * @param __svt An object convertible to string_view containing
+ * characters to locate.
+ * @param __pos Index of character to search from (default 0).
+ * @return Index of first occurrence.
+ */
+ template<typename _Tp>
+ _If_sv<_Tp, size_type>
+ find_first_of(const _Tp& __svt, size_type __pos = 0) const
+ noexcept(is_same<_Tp, __sv_type>::value)
+ {
+ __sv_type __sv = __svt;
+ return this->find_first_of(__sv.data(), __pos, __sv.size());
+ }
+#endif // C++17
+
+ /**
+ * @brief Find last position of a character of string.
+ * @param __str String containing characters to locate.
+ * @param __pos Index of character to search back from (default end).
+ * @return Index of last occurrence.
+ *
+ * Starting from @a __pos, searches backward for one of the
+ * characters of @a __str within this string. If found,
+ * returns the index where it was found. If not found, returns
+ * npos.
+ */
+ size_type
+ find_last_of(const basic_string& __str, size_type __pos = npos) const
+ _GLIBCXX_NOEXCEPT
+ { return this->find_last_of(__str.data(), __pos, __str.size()); }
+
+ /**
+ * @brief Find last position of a character of C substring.
+ * @param __s C string containing characters to locate.
+ * @param __pos Index of character to search back from.
+ * @param __n Number of characters from s to search for.
+ * @return Index of last occurrence.
+ *
+ * Starting from @a __pos, searches backward for one of the
+ * first @a __n characters of @a __s within this string. If
+ * found, returns the index where it was found. If not found,
+ * returns npos.
+ */
+ size_type
+ find_last_of(const _CharT* __s, size_type __pos, size_type __n) const
+ _GLIBCXX_NOEXCEPT;
+
+ /**
+ * @brief Find last position of a character of C string.
+ * @param __s C string containing characters to locate.
+ * @param __pos Index of character to search back from (default end).
+ * @return Index of last occurrence.
+ *
+ * Starting from @a __pos, searches backward for one of the
+ * characters of @a __s within this string. If found, returns
+ * the index where it was found. If not found, returns npos.
+ */
+ size_type
+ find_last_of(const _CharT* __s, size_type __pos = npos) const
+ _GLIBCXX_NOEXCEPT
+ {
+ __glibcxx_requires_string(__s);
+ return this->find_last_of(__s, __pos, traits_type::length(__s));
+ }
+
+ /**
+ * @brief Find last position of a character.
+ * @param __c Character to locate.
+ * @param __pos Index of character to search back from (default end).
+ * @return Index of last occurrence.
+ *
+ * Starting from @a __pos, searches backward for @a __c within
+ * this string. If found, returns the index where it was
+ * found. If not found, returns npos.
+ *
+ * Note: equivalent to rfind(__c, __pos).
+ */
+ size_type
+ find_last_of(_CharT __c, size_type __pos = npos) const _GLIBCXX_NOEXCEPT
+ { return this->rfind(__c, __pos); }
+
+#if __cplusplus >= 201703L
+ /**
+ * @brief Find last position of a character of string.
+ * @param __svt An object convertible to string_view containing
+ * characters to locate.
+ * @param __pos Index of character to search back from (default end).
+ * @return Index of last occurrence.
+ */
+ template<typename _Tp>
+ _If_sv<_Tp, size_type>
+ find_last_of(const _Tp& __svt, size_type __pos = npos) const
+ noexcept(is_same<_Tp, __sv_type>::value)
+ {
+ __sv_type __sv = __svt;
+ return this->find_last_of(__sv.data(), __pos, __sv.size());
+ }
+#endif // C++17
+
+ /**
+ * @brief Find position of a character not in string.
+ * @param __str String containing characters to avoid.
+ * @param __pos Index of character to search from (default 0).
+ * @return Index of first occurrence.
+ *
+ * Starting from @a __pos, searches forward for a character not contained
+ * in @a __str within this string. If found, returns the index where it
+ * was found. If not found, returns npos.
+ */
+ size_type
+ find_first_not_of(const basic_string& __str, size_type __pos = 0) const
+ _GLIBCXX_NOEXCEPT
+ { return this->find_first_not_of(__str.data(), __pos, __str.size()); }
+
+ /**
+ * @brief Find position of a character not in C substring.
+ * @param __s C string containing characters to avoid.
+ * @param __pos Index of character to search from.
+ * @param __n Number of characters from __s to consider.
+ * @return Index of first occurrence.
+ *
+ * Starting from @a __pos, searches forward for a character not
+ * contained in the first @a __n characters of @a __s within
+ * this string. If found, returns the index where it was
+ * found. If not found, returns npos.
+ */
+ size_type
+ find_first_not_of(const _CharT* __s, size_type __pos,
+ size_type __n) const _GLIBCXX_NOEXCEPT;
+
+ /**
+ * @brief Find position of a character not in C string.
+ * @param __s C string containing characters to avoid.
+ * @param __pos Index of character to search from (default 0).
+ * @return Index of first occurrence.
+ *
+ * Starting from @a __pos, searches forward for a character not
+ * contained in @a __s within this string. If found, returns
+ * the index where it was found. If not found, returns npos.
+ */
+ size_type
+ find_first_not_of(const _CharT* __s, size_type __pos = 0) const
+ _GLIBCXX_NOEXCEPT
+ {
+ __glibcxx_requires_string(__s);
+ return this->find_first_not_of(__s, __pos, traits_type::length(__s));
+ }
+
+ /**
+ * @brief Find position of a different character.
+ * @param __c Character to avoid.
+ * @param __pos Index of character to search from (default 0).
+ * @return Index of first occurrence.
+ *
+ * Starting from @a __pos, searches forward for a character
+ * other than @a __c within this string. If found, returns the
+ * index where it was found. If not found, returns npos.
+ */
+ size_type
+ find_first_not_of(_CharT __c, size_type __pos = 0) const
+ _GLIBCXX_NOEXCEPT;
+
+#if __cplusplus >= 201703L
+ /**
+ * @brief Find position of a character not in a string_view.
+ * @param __svt An object convertible to string_view containing
+ * characters to avoid.
+ * @param __pos Index of character to search from (default 0).
+ * @return Index of first occurrence.
+ */
+ template<typename _Tp>
+ _If_sv<_Tp, size_type>
+ find_first_not_of(const _Tp& __svt, size_type __pos = 0) const
+ noexcept(is_same<_Tp, __sv_type>::value)
+ {
+ __sv_type __sv = __svt;
+ return this->find_first_not_of(__sv.data(), __pos, __sv.size());
+ }
+#endif // C++17
+
+ /**
+ * @brief Find last position of a character not in string.
+ * @param __str String containing characters to avoid.
+ * @param __pos Index of character to search back from (default end).
+ * @return Index of last occurrence.
+ *
+ * Starting from @a __pos, searches backward for a character
+ * not contained in @a __str within this string. If found,
+ * returns the index where it was found. If not found, returns
+ * npos.
+ */
+ size_type
+ find_last_not_of(const basic_string& __str, size_type __pos = npos) const
+ _GLIBCXX_NOEXCEPT
+ { return this->find_last_not_of(__str.data(), __pos, __str.size()); }
+
+ /**
+ * @brief Find last position of a character not in C substring.
+ * @param __s C string containing characters to avoid.
+ * @param __pos Index of character to search back from.
+ * @param __n Number of characters from s to consider.
+ * @return Index of last occurrence.
+ *
+ * Starting from @a __pos, searches backward for a character not
+ * contained in the first @a __n characters of @a __s within this string.
+ * If found, returns the index where it was found. If not found,
+ * returns npos.
+ */
+ size_type
+ find_last_not_of(const _CharT* __s, size_type __pos,
+ size_type __n) const _GLIBCXX_NOEXCEPT;
+ /**
+ * @brief Find last position of a character not in C string.
+ * @param __s C string containing characters to avoid.
+ * @param __pos Index of character to search back from (default end).
+ * @return Index of last occurrence.
+ *
+ * Starting from @a __pos, searches backward for a character
+ * not contained in @a __s within this string. If found,
+ * returns the index where it was found. If not found, returns
+ * npos.
+ */
+ size_type
+ find_last_not_of(const _CharT* __s, size_type __pos = npos) const
+ _GLIBCXX_NOEXCEPT
+ {
+ __glibcxx_requires_string(__s);
+ return this->find_last_not_of(__s, __pos, traits_type::length(__s));
+ }
+
+ /**
+ * @brief Find last position of a different character.
+ * @param __c Character to avoid.
+ * @param __pos Index of character to search back from (default end).
+ * @return Index of last occurrence.
+ *
+ * Starting from @a __pos, searches backward for a character other than
+ * @a __c within this string. If found, returns the index where it was
+ * found. If not found, returns npos.
+ */
+ size_type
+ find_last_not_of(_CharT __c, size_type __pos = npos) const
+ _GLIBCXX_NOEXCEPT;
+
+#if __cplusplus >= 201703L
+ /**
+ * @brief Find last position of a character not in a string_view.
+ * @param __svt An object convertible to string_view containing
+ * characters to avoid.
+ * @param __pos Index of character to search back from (default end).
+ * @return Index of last occurrence.
+ */
+ template<typename _Tp>
+ _If_sv<_Tp, size_type>
+ find_last_not_of(const _Tp& __svt, size_type __pos = npos) const
+ noexcept(is_same<_Tp, __sv_type>::value)
+ {
+ __sv_type __sv = __svt;
+ return this->find_last_not_of(__sv.data(), __pos, __sv.size());
+ }
+#endif // C++17
+
+ /**
+ * @brief Get a substring.
+ * @param __pos Index of first character (default 0).
+ * @param __n Number of characters in substring (default remainder).
+ * @return The new string.
+ * @throw std::out_of_range If __pos > size().
+ *
+ * Construct and return a new string using the @a __n
+ * characters starting at @a __pos. If the string is too
+ * short, use the remainder of the characters. If @a __pos is
+ * beyond the end of the string, out_of_range is thrown.
+ */
+ basic_string
+ substr(size_type __pos = 0, size_type __n = npos) const
+ { return basic_string(*this,
+ _M_check(__pos, "basic_string::substr"), __n); }
+
+ /**
+ * @brief Compare to a string.
+ * @param __str String to compare against.
+ * @return Integer < 0, 0, or > 0.
+ *
+ * Returns an integer < 0 if this string is ordered before @a
+ * __str, 0 if their values are equivalent, or > 0 if this
+ * string is ordered after @a __str. Determines the effective
+ * length rlen of the strings to compare as the smallest of
+ * size() and str.size(). The function then compares the two
+ * strings by calling traits::compare(data(), str.data(),rlen).
+ * If the result of the comparison is nonzero returns it,
+ * otherwise the shorter one is ordered first.
+ */
+ int
+ compare(const basic_string& __str) const
+ {
+ const size_type __size = this->size();
+ const size_type __osize = __str.size();
+ const size_type __len = std::min(__size, __osize);
+
+ int __r = traits_type::compare(_M_data(), __str.data(), __len);
+ if (!__r)
+ __r = _S_compare(__size, __osize);
+ return __r;
+ }
+
+#if __cplusplus >= 201703L
+ /**
+ * @brief Compare to a string_view.
+ * @param __svt An object convertible to string_view to compare against.
+ * @return Integer < 0, 0, or > 0.
+ */
+ template<typename _Tp>
+ _If_sv<_Tp, int>
+ compare(const _Tp& __svt) const
+ noexcept(is_same<_Tp, __sv_type>::value)
+ {
+ __sv_type __sv = __svt;
+ const size_type __size = this->size();
+ const size_type __osize = __sv.size();
+ const size_type __len = std::min(__size, __osize);
+
+ int __r = traits_type::compare(_M_data(), __sv.data(), __len);
+ if (!__r)
+ __r = _S_compare(__size, __osize);
+ return __r;
+ }
+
+ /**
+ * @brief Compare to a string_view.
+ * @param __pos A position in the string to start comparing from.
+ * @param __n The number of characters to compare.
+ * @param __svt An object convertible to string_view to compare
+ * against.
+ * @return Integer < 0, 0, or > 0.
+ */
+ template<typename _Tp>
+ _If_sv<_Tp, int>
+ compare(size_type __pos, size_type __n, const _Tp& __svt) const
+ noexcept(is_same<_Tp, __sv_type>::value)
+ {
+ __sv_type __sv = __svt;
+ return __sv_type(*this).substr(__pos, __n).compare(__sv);
+ }
+
+ /**
+ * @brief Compare to a string_view.
+ * @param __pos1 A position in the string to start comparing from.
+ * @param __n1 The number of characters to compare.
+ * @param __svt An object convertible to string_view to compare
+ * against.
+ * @param __pos2 A position in the string_view to start comparing from.
+ * @param __n2 The number of characters to compare.
+ * @return Integer < 0, 0, or > 0.
+ */
+ template<typename _Tp>
+ _If_sv<_Tp, int>
+ compare(size_type __pos1, size_type __n1, const _Tp& __svt,
+ size_type __pos2, size_type __n2 = npos) const
+ noexcept(is_same<_Tp, __sv_type>::value)
+ {
+ __sv_type __sv = __svt;
+ return __sv_type(*this)
+ .substr(__pos1, __n1).compare(__sv.substr(__pos2, __n2));
+ }
+#endif // C++17
+
+ /**
+ * @brief Compare substring to a string.
+ * @param __pos Index of first character of substring.
+ * @param __n Number of characters in substring.
+ * @param __str String to compare against.
+ * @return Integer < 0, 0, or > 0.
+ *
+ * Form the substring of this string from the @a __n characters
+ * starting at @a __pos. Returns an integer < 0 if the
+ * substring is ordered before @a __str, 0 if their values are
+ * equivalent, or > 0 if the substring is ordered after @a
+ * __str. Determines the effective length rlen of the strings
+ * to compare as the smallest of the length of the substring
+ * and @a __str.size(). The function then compares the two
+ * strings by calling
+ * traits::compare(substring.data(),str.data(),rlen). If the
+ * result of the comparison is nonzero returns it, otherwise
+ * the shorter one is ordered first.
+ */
+ int
+ compare(size_type __pos, size_type __n, const basic_string& __str) const;
+
+ /**
+ * @brief Compare substring to a substring.
+ * @param __pos1 Index of first character of substring.
+ * @param __n1 Number of characters in substring.
+ * @param __str String to compare against.
+ * @param __pos2 Index of first character of substring of str.
+ * @param __n2 Number of characters in substring of str.
+ * @return Integer < 0, 0, or > 0.
+ *
+ * Form the substring of this string from the @a __n1
+ * characters starting at @a __pos1. Form the substring of @a
+ * __str from the @a __n2 characters starting at @a __pos2.
+ * Returns an integer < 0 if this substring is ordered before
+ * the substring of @a __str, 0 if their values are equivalent,
+ * or > 0 if this substring is ordered after the substring of
+ * @a __str. Determines the effective length rlen of the
+ * strings to compare as the smallest of the lengths of the
+ * substrings. The function then compares the two strings by
+ * calling
+ * traits::compare(substring.data(),str.substr(pos2,n2).data(),rlen).
+ * If the result of the comparison is nonzero returns it,
+ * otherwise the shorter one is ordered first.
+ */
+ int
+ compare(size_type __pos1, size_type __n1, const basic_string& __str,
+ size_type __pos2, size_type __n2 = npos) const;
+
+ /**
+ * @brief Compare to a C string.
+ * @param __s C string to compare against.
+ * @return Integer < 0, 0, or > 0.
+ *
+ * Returns an integer < 0 if this string is ordered before @a __s, 0 if
+ * their values are equivalent, or > 0 if this string is ordered after
+ * @a __s. Determines the effective length rlen of the strings to
+ * compare as the smallest of size() and the length of a string
+ * constructed from @a __s. The function then compares the two strings
+ * by calling traits::compare(data(),s,rlen). If the result of the
+ * comparison is nonzero returns it, otherwise the shorter one is
+ * ordered first.
+ */
+ int
+ compare(const _CharT* __s) const _GLIBCXX_NOEXCEPT;
+
+ // _GLIBCXX_RESOLVE_LIB_DEFECTS
+ // 5 String::compare specification questionable
+ /**
+ * @brief Compare substring to a C string.
+ * @param __pos Index of first character of substring.
+ * @param __n1 Number of characters in substring.
+ * @param __s C string to compare against.
+ * @return Integer < 0, 0, or > 0.
+ *
+ * Form the substring of this string from the @a __n1
+ * characters starting at @a pos. Returns an integer < 0 if
+ * the substring is ordered before @a __s, 0 if their values
+ * are equivalent, or > 0 if the substring is ordered after @a
+ * __s. Determines the effective length rlen of the strings to
+ * compare as the smallest of the length of the substring and
+ * the length of a string constructed from @a __s. The
+ * function then compares the two string by calling
+ * traits::compare(substring.data(),__s,rlen). If the result of
+ * the comparison is nonzero returns it, otherwise the shorter
+ * one is ordered first.
+ */
+ int
+ compare(size_type __pos, size_type __n1, const _CharT* __s) const;
+
+ /**
+ * @brief Compare substring against a character %array.
+ * @param __pos Index of first character of substring.
+ * @param __n1 Number of characters in substring.
+ * @param __s character %array to compare against.
+ * @param __n2 Number of characters of s.
+ * @return Integer < 0, 0, or > 0.
+ *
+ * Form the substring of this string from the @a __n1
+ * characters starting at @a __pos. Form a string from the
+ * first @a __n2 characters of @a __s. Returns an integer < 0
+ * if this substring is ordered before the string from @a __s,
+ * 0 if their values are equivalent, or > 0 if this substring
+ * is ordered after the string from @a __s. Determines the
+ * effective length rlen of the strings to compare as the
+ * smallest of the length of the substring and @a __n2. The
+ * function then compares the two strings by calling
+ * traits::compare(substring.data(),s,rlen). If the result of
+ * the comparison is nonzero returns it, otherwise the shorter
+ * one is ordered first.
+ *
+ * NB: s must have at least n2 characters, '\\0' has
+ * no special meaning.
+ */
+ int
+ compare(size_type __pos, size_type __n1, const _CharT* __s,
+ size_type __n2) const;
+
+#if __cplusplus > 201703L
+ bool
+ starts_with(basic_string_view<_CharT, _Traits> __x) const noexcept
+ { return __sv_type(this->data(), this->size()).starts_with(__x); }
+
+ bool
+ starts_with(_CharT __x) const noexcept
+ { return __sv_type(this->data(), this->size()).starts_with(__x); }
+
+ bool
+ starts_with(const _CharT* __x) const noexcept
+ { return __sv_type(this->data(), this->size()).starts_with(__x); }
+
+ bool
+ ends_with(basic_string_view<_CharT, _Traits> __x) const noexcept
+ { return __sv_type(this->data(), this->size()).ends_with(__x); }
+
+ bool
+ ends_with(_CharT __x) const noexcept
+ { return __sv_type(this->data(), this->size()).ends_with(__x); }
+
+ bool
+ ends_with(const _CharT* __x) const noexcept
+ { return __sv_type(this->data(), this->size()).ends_with(__x); }
+#endif // C++20
+
+#if __cplusplus >= 202011L \
+ || (__cplusplus == 202002L && !defined __STRICT_ANSI__)
+ bool
+ contains(basic_string_view<_CharT, _Traits> __x) const noexcept
+ { return __sv_type(this->data(), this->size()).contains(__x); }
+
+ bool
+ contains(_CharT __x) const noexcept
+ { return __sv_type(this->data(), this->size()).contains(__x); }
+
+ bool
+ contains(const _CharT* __x) const noexcept
+ { return __sv_type(this->data(), this->size()).contains(__x); }
+#endif // C++23
+
+# ifdef _GLIBCXX_TM_TS_INTERNAL
+ friend void
+ ::_txnal_cow_string_C1_for_exceptions(void* that, const char* s,
+ void* exc);
+ friend const char*
+ ::_txnal_cow_string_c_str(const void *that);
+ friend void
+ ::_txnal_cow_string_D1(void *that);
+ friend void
+ ::_txnal_cow_string_D1_commit(void *that);
+# endif
+ };
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ const typename basic_string<_CharT, _Traits, _Alloc>::size_type
+ basic_string<_CharT, _Traits, _Alloc>::
+ _Rep::_S_max_size = (((npos - sizeof(_Rep_base))/sizeof(_CharT)) - 1) / 4;
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ const _CharT
+ basic_string<_CharT, _Traits, _Alloc>::
+ _Rep::_S_terminal = _CharT();
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ const typename basic_string<_CharT, _Traits, _Alloc>::size_type
+ basic_string<_CharT, _Traits, _Alloc>::npos;
+
+ // Linker sets _S_empty_rep_storage to all 0s (one reference, empty string)
+ // at static init time (before static ctors are run).
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ typename basic_string<_CharT, _Traits, _Alloc>::size_type
+ basic_string<_CharT, _Traits, _Alloc>::_Rep::_S_empty_rep_storage[
+ (sizeof(_Rep_base) + sizeof(_CharT) + sizeof(size_type) - 1) /
+ sizeof(size_type)];
+
+ // NB: This is the special case for Input Iterators, used in
+ // istreambuf_iterators, etc.
+ // Input Iterators have a cost structure very different from
+ // pointers, calling for a different coding style.
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ template<typename _InIterator>
+ _CharT*
+ basic_string<_CharT, _Traits, _Alloc>::
+ _S_construct(_InIterator __beg, _InIterator __end, const _Alloc& __a,
+ input_iterator_tag)
+ {
+#if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
+ if (__beg == __end && __a == _Alloc())
+ return _S_empty_rep()._M_refdata();
+#endif
+ // Avoid reallocation for common case.
+ _CharT __buf[128];
+ size_type __len = 0;
+ while (__beg != __end && __len < sizeof(__buf) / sizeof(_CharT))
+ {
+ __buf[__len++] = *__beg;
+ ++__beg;
+ }
+ _Rep* __r = _Rep::_S_create(__len, size_type(0), __a);
+ _M_copy(__r->_M_refdata(), __buf, __len);
+ __try
+ {
+ while (__beg != __end)
+ {
+ if (__len == __r->_M_capacity)
+ {
+ // Allocate more space.
+ _Rep* __another = _Rep::_S_create(__len + 1, __len, __a);
+ _M_copy(__another->_M_refdata(), __r->_M_refdata(), __len);
+ __r->_M_destroy(__a);
+ __r = __another;
+ }
+ __r->_M_refdata()[__len++] = *__beg;
+ ++__beg;
+ }
+ }
+ __catch(...)
+ {
+ __r->_M_destroy(__a);
+ __throw_exception_again;
+ }
+ __r->_M_set_length_and_sharable(__len);
+ return __r->_M_refdata();
+ }
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ template <typename _InIterator>
+ _CharT*
+ basic_string<_CharT, _Traits, _Alloc>::
+ _S_construct(_InIterator __beg, _InIterator __end, const _Alloc& __a,
+ forward_iterator_tag)
+ {
+#if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
+ if (__beg == __end && __a == _Alloc())
+ return _S_empty_rep()._M_refdata();
+#endif
+ // NB: Not required, but considered best practice.
+ if (__gnu_cxx::__is_null_pointer(__beg) && __beg != __end)
+ __throw_logic_error(__N("basic_string::_S_construct null not valid"));
+
+ const size_type __dnew = static_cast<size_type>(std::distance(__beg,
+ __end));
+ // Check for out_of_range and length_error exceptions.
+ _Rep* __r = _Rep::_S_create(__dnew, size_type(0), __a);
+ __try
+ { _S_copy_chars(__r->_M_refdata(), __beg, __end); }
+ __catch(...)
+ {
+ __r->_M_destroy(__a);
+ __throw_exception_again;
+ }
+ __r->_M_set_length_and_sharable(__dnew);
+ return __r->_M_refdata();
+ }
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ _CharT*
+ basic_string<_CharT, _Traits, _Alloc>::
+ _S_construct(size_type __n, _CharT __c, const _Alloc& __a)
+ {
+#if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
+ if (__n == 0 && __a == _Alloc())
+ return _S_empty_rep()._M_refdata();
+#endif
+ // Check for out_of_range and length_error exceptions.
+ _Rep* __r = _Rep::_S_create(__n, size_type(0), __a);
+ if (__n)
+ _M_assign(__r->_M_refdata(), __n, __c);
+
+ __r->_M_set_length_and_sharable(__n);
+ return __r->_M_refdata();
+ }
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ basic_string<_CharT, _Traits, _Alloc>::
+ basic_string(const basic_string& __str, size_type __pos, const _Alloc& __a)
+ : _M_dataplus(_S_construct(__str._M_data()
+ + __str._M_check(__pos,
+ "basic_string::basic_string"),
+ __str._M_data() + __str._M_limit(__pos, npos)
+ + __pos, __a), __a)
+ { }
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ basic_string<_CharT, _Traits, _Alloc>::
+ basic_string(const basic_string& __str, size_type __pos, size_type __n)
+ : _M_dataplus(_S_construct(__str._M_data()
+ + __str._M_check(__pos,
+ "basic_string::basic_string"),
+ __str._M_data() + __str._M_limit(__pos, __n)
+ + __pos, _Alloc()), _Alloc())
+ { }
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ basic_string<_CharT, _Traits, _Alloc>::
+ basic_string(const basic_string& __str, size_type __pos,
+ size_type __n, const _Alloc& __a)
+ : _M_dataplus(_S_construct(__str._M_data()
+ + __str._M_check(__pos,
+ "basic_string::basic_string"),
+ __str._M_data() + __str._M_limit(__pos, __n)
+ + __pos, __a), __a)
+ { }
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ basic_string<_CharT, _Traits, _Alloc>&
+ basic_string<_CharT, _Traits, _Alloc>::
+ assign(const basic_string& __str)
+ {
+ if (_M_rep() != __str._M_rep())
+ {
+ // XXX MT
+ const allocator_type __a = this->get_allocator();
+ _CharT* __tmp = __str._M_rep()->_M_grab(__a, __str.get_allocator());
+ _M_rep()->_M_dispose(__a);
+ _M_data(__tmp);
+ }
+ return *this;
+ }
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ basic_string<_CharT, _Traits, _Alloc>&
+ basic_string<_CharT, _Traits, _Alloc>::
+ assign(const _CharT* __s, size_type __n)
+ {
+ __glibcxx_requires_string_len(__s, __n);
+ _M_check_length(this->size(), __n, "basic_string::assign");
+ if (_M_disjunct(__s) || _M_rep()->_M_is_shared())
+ return _M_replace_safe(size_type(0), this->size(), __s, __n);
+ else
+ {
+ // Work in-place.
+ const size_type __pos = __s - _M_data();
+ if (__pos >= __n)
+ _M_copy(_M_data(), __s, __n);
+ else if (__pos)
+ _M_move(_M_data(), __s, __n);
+ _M_rep()->_M_set_length_and_sharable(__n);
+ return *this;
+ }
+ }
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ basic_string<_CharT, _Traits, _Alloc>&
+ basic_string<_CharT, _Traits, _Alloc>::
+ append(size_type __n, _CharT __c)
+ {
+ if (__n)
+ {
+ _M_check_length(size_type(0), __n, "basic_string::append");
+ const size_type __len = __n + this->size();
+ if (__len > this->capacity() || _M_rep()->_M_is_shared())
+ this->reserve(__len);
+ _M_assign(_M_data() + this->size(), __n, __c);
+ _M_rep()->_M_set_length_and_sharable(__len);
+ }
+ return *this;
+ }
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ basic_string<_CharT, _Traits, _Alloc>&
+ basic_string<_CharT, _Traits, _Alloc>::
+ append(const _CharT* __s, size_type __n)
+ {
+ __glibcxx_requires_string_len(__s, __n);
+ if (__n)
+ {
+ _M_check_length(size_type(0), __n, "basic_string::append");
+ const size_type __len = __n + this->size();
+ if (__len > this->capacity() || _M_rep()->_M_is_shared())
+ {
+ if (_M_disjunct(__s))
+ this->reserve(__len);
+ else
+ {
+ const size_type __off = __s - _M_data();
+ this->reserve(__len);
+ __s = _M_data() + __off;
+ }
+ }
+ _M_copy(_M_data() + this->size(), __s, __n);
+ _M_rep()->_M_set_length_and_sharable(__len);
+ }
+ return *this;
+ }
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ basic_string<_CharT, _Traits, _Alloc>&
+ basic_string<_CharT, _Traits, _Alloc>::
+ append(const basic_string& __str)
+ {
+ const size_type __size = __str.size();
+ if (__size)
+ {
+ const size_type __len = __size + this->size();
+ if (__len > this->capacity() || _M_rep()->_M_is_shared())
+ this->reserve(__len);
+ _M_copy(_M_data() + this->size(), __str._M_data(), __size);
+ _M_rep()->_M_set_length_and_sharable(__len);
+ }
+ return *this;
+ }
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ basic_string<_CharT, _Traits, _Alloc>&
+ basic_string<_CharT, _Traits, _Alloc>::
+ append(const basic_string& __str, size_type __pos, size_type __n)
+ {
+ __str._M_check(__pos, "basic_string::append");
+ __n = __str._M_limit(__pos, __n);
+ if (__n)
+ {
+ const size_type __len = __n + this->size();
+ if (__len > this->capacity() || _M_rep()->_M_is_shared())
+ this->reserve(__len);
+ _M_copy(_M_data() + this->size(), __str._M_data() + __pos, __n);
+ _M_rep()->_M_set_length_and_sharable(__len);
+ }
+ return *this;
+ }
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ basic_string<_CharT, _Traits, _Alloc>&
+ basic_string<_CharT, _Traits, _Alloc>::
+ insert(size_type __pos, const _CharT* __s, size_type __n)
+ {
+ __glibcxx_requires_string_len(__s, __n);
+ _M_check(__pos, "basic_string::insert");
+ _M_check_length(size_type(0), __n, "basic_string::insert");
+ if (_M_disjunct(__s) || _M_rep()->_M_is_shared())
+ return _M_replace_safe(__pos, size_type(0), __s, __n);
+ else
+ {
+ // Work in-place.
+ const size_type __off = __s - _M_data();
+ _M_mutate(__pos, 0, __n);
+ __s = _M_data() + __off;
+ _CharT* __p = _M_data() + __pos;
+ if (__s + __n <= __p)
+ _M_copy(__p, __s, __n);
+ else if (__s >= __p)
+ _M_copy(__p, __s + __n, __n);
+ else
+ {
+ const size_type __nleft = __p - __s;
+ _M_copy(__p, __s, __nleft);
+ _M_copy(__p + __nleft, __p + __n, __n - __nleft);
+ }
+ return *this;
+ }
+ }
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ typename basic_string<_CharT, _Traits, _Alloc>::iterator
+ basic_string<_CharT, _Traits, _Alloc>::
+ erase(iterator __first, iterator __last)
+ {
+ _GLIBCXX_DEBUG_PEDASSERT(__first >= _M_ibegin() && __first <= __last
+ && __last <= _M_iend());
+
+ // NB: This isn't just an optimization (bail out early when
+ // there is nothing to do, really), it's also a correctness
+ // issue vs MT, see libstdc++/40518.
+ const size_type __size = __last - __first;
+ if (__size)
+ {
+ const size_type __pos = __first - _M_ibegin();
+ _M_mutate(__pos, __size, size_type(0));
+ _M_rep()->_M_set_leaked();
+ return iterator(_M_data() + __pos);
+ }
+ else
+ return __first;
+ }
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ basic_string<_CharT, _Traits, _Alloc>&
+ basic_string<_CharT, _Traits, _Alloc>::
+ replace(size_type __pos, size_type __n1, const _CharT* __s,
+ size_type __n2)
+ {
+ __glibcxx_requires_string_len(__s, __n2);
+ _M_check(__pos, "basic_string::replace");
+ __n1 = _M_limit(__pos, __n1);
+ _M_check_length(__n1, __n2, "basic_string::replace");
+ bool __left;
+ if (_M_disjunct(__s) || _M_rep()->_M_is_shared())
+ return _M_replace_safe(__pos, __n1, __s, __n2);
+ else if ((__left = __s + __n2 <= _M_data() + __pos)
+ || _M_data() + __pos + __n1 <= __s)
+ {
+ // Work in-place: non-overlapping case.
+ size_type __off = __s - _M_data();
+ __left ? __off : (__off += __n2 - __n1);
+ _M_mutate(__pos, __n1, __n2);
+ _M_copy(_M_data() + __pos, _M_data() + __off, __n2);
+ return *this;
+ }
+ else
+ {
+ // Todo: overlapping case.
+ const basic_string __tmp(__s, __n2);
+ return _M_replace_safe(__pos, __n1, __tmp._M_data(), __n2);
+ }
+ }
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ void
+ basic_string<_CharT, _Traits, _Alloc>::_Rep::
+ _M_destroy(const _Alloc& __a) throw ()
+ {
+ const size_type __size = sizeof(_Rep_base) +
+ (this->_M_capacity + 1) * sizeof(_CharT);
+ _Raw_bytes_alloc(__a).deallocate(reinterpret_cast<char*>(this), __size);
+ }
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ void
+ basic_string<_CharT, _Traits, _Alloc>::
+ _M_leak_hard()
+ {
+#if _GLIBCXX_FULLY_DYNAMIC_STRING == 0
+ if (_M_rep() == &_S_empty_rep())
+ return;
+#endif
+ if (_M_rep()->_M_is_shared())
+ _M_mutate(0, 0, 0);
+ _M_rep()->_M_set_leaked();
+ }
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ void
+ basic_string<_CharT, _Traits, _Alloc>::
+ _M_mutate(size_type __pos, size_type __len1, size_type __len2)
+ {
+ const size_type __old_size = this->size();
+ const size_type __new_size = __old_size + __len2 - __len1;
+ const size_type __how_much = __old_size - __pos - __len1;
+
+ if (__new_size > this->capacity() || _M_rep()->_M_is_shared())
+ {
+ // Must reallocate.
+ const allocator_type __a = get_allocator();
+ _Rep* __r = _Rep::_S_create(__new_size, this->capacity(), __a);
+
+ if (__pos)
+ _M_copy(__r->_M_refdata(), _M_data(), __pos);
+ if (__how_much)
+ _M_copy(__r->_M_refdata() + __pos + __len2,
+ _M_data() + __pos + __len1, __how_much);
+
+ _M_rep()->_M_dispose(__a);
+ _M_data(__r->_M_refdata());
+ }
+ else if (__how_much && __len1 != __len2)
+ {
+ // Work in-place.
+ _M_move(_M_data() + __pos + __len2,
+ _M_data() + __pos + __len1, __how_much);
+ }
+ _M_rep()->_M_set_length_and_sharable(__new_size);
+ }
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ void
+ basic_string<_CharT, _Traits, _Alloc>::
+ reserve(size_type __res)
+ {
+ const size_type __capacity = capacity();
+
+ // _GLIBCXX_RESOLVE_LIB_DEFECTS
+ // 2968. Inconsistencies between basic_string reserve and
+ // vector/unordered_map/unordered_set reserve functions
+ // P0966 reserve should not shrink
+ if (__res <= __capacity)
+ {
+ if (!_M_rep()->_M_is_shared())
+ return;
+
+ // unshare, but keep same capacity
+ __res = __capacity;
+ }
+
+ const allocator_type __a = get_allocator();
+ _CharT* __tmp = _M_rep()->_M_clone(__a, __res - this->size());
+ _M_rep()->_M_dispose(__a);
+ _M_data(__tmp);
+ }
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ void
+ basic_string<_CharT, _Traits, _Alloc>::
+ swap(basic_string& __s)
+ _GLIBCXX_NOEXCEPT_IF(allocator_traits<_Alloc>::is_always_equal::value)
+ {
+ if (_M_rep()->_M_is_leaked())
+ _M_rep()->_M_set_sharable();
+ if (__s._M_rep()->_M_is_leaked())
+ __s._M_rep()->_M_set_sharable();
+ if (this->get_allocator() == __s.get_allocator())
+ {
+ _CharT* __tmp = _M_data();
+ _M_data(__s._M_data());
+ __s._M_data(__tmp);
+ }
+ // The code below can usually be optimized away.
+ else
+ {
+ const basic_string __tmp1(_M_ibegin(), _M_iend(),
+ __s.get_allocator());
+ const basic_string __tmp2(__s._M_ibegin(), __s._M_iend(),
+ this->get_allocator());
+ *this = __tmp2;
+ __s = __tmp1;
+ }
+ }
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ typename basic_string<_CharT, _Traits, _Alloc>::_Rep*
+ basic_string<_CharT, _Traits, _Alloc>::_Rep::
+ _S_create(size_type __capacity, size_type __old_capacity,
+ const _Alloc& __alloc)
+ {
+ // _GLIBCXX_RESOLVE_LIB_DEFECTS
+ // 83. String::npos vs. string::max_size()
+ if (__capacity > _S_max_size)
+ __throw_length_error(__N("basic_string::_S_create"));
+
+ // The standard places no restriction on allocating more memory
+ // than is strictly needed within this layer at the moment or as
+ // requested by an explicit application call to reserve(n).
+
+ // Many malloc implementations perform quite poorly when an
+ // application attempts to allocate memory in a stepwise fashion
+ // growing each allocation size by only 1 char. Additionally,
+ // it makes little sense to allocate less linear memory than the
+ // natural blocking size of the malloc implementation.
+ // Unfortunately, we would need a somewhat low-level calculation
+ // with tuned parameters to get this perfect for any particular
+ // malloc implementation. Fortunately, generalizations about
+ // common features seen among implementations seems to suffice.
+
+ // __pagesize need not match the actual VM page size for good
+ // results in practice, thus we pick a common value on the low
+ // side. __malloc_header_size is an estimate of the amount of
+ // overhead per memory allocation (in practice seen N * sizeof
+ // (void*) where N is 0, 2 or 4). According to folklore,
+ // picking this value on the high side is better than
+ // low-balling it (especially when this algorithm is used with
+ // malloc implementations that allocate memory blocks rounded up
+ // to a size which is a power of 2).
+ const size_type __pagesize = 4096;
+ const size_type __malloc_header_size = 4 * sizeof(void*);
+
+ // The below implements an exponential growth policy, necessary to
+ // meet amortized linear time requirements of the library: see
+ // http://gcc.gnu.org/ml/libstdc++/2001-07/msg00085.html.
+ // It's active for allocations requiring an amount of memory above
+ // system pagesize. This is consistent with the requirements of the
+ // standard: http://gcc.gnu.org/ml/libstdc++/2001-07/msg00130.html
+ if (__capacity > __old_capacity && __capacity < 2 * __old_capacity)
+ __capacity = 2 * __old_capacity;
+
+ // NB: Need an array of char_type[__capacity], plus a terminating
+ // null char_type() element, plus enough for the _Rep data structure.
+ // Whew. Seemingly so needy, yet so elemental.
+ size_type __size = (__capacity + 1) * sizeof(_CharT) + sizeof(_Rep);
+
+ const size_type __adj_size = __size + __malloc_header_size;
+ if (__adj_size > __pagesize && __capacity > __old_capacity)
+ {
+ const size_type __extra = __pagesize - __adj_size % __pagesize;
+ __capacity += __extra / sizeof(_CharT);
+ // Never allocate a string bigger than _S_max_size.
+ if (__capacity > _S_max_size)
+ __capacity = _S_max_size;
+ __size = (__capacity + 1) * sizeof(_CharT) + sizeof(_Rep);
+ }
+
+ // NB: Might throw, but no worries about a leak, mate: _Rep()
+ // does not throw.
+ void* __place = _Raw_bytes_alloc(__alloc).allocate(__size);
+ _Rep *__p = new (__place) _Rep;
+ __p->_M_capacity = __capacity;
+ // ABI compatibility - 3.4.x set in _S_create both
+ // _M_refcount and _M_length. All callers of _S_create
+ // in basic_string.tcc then set just _M_length.
+ // In 4.0.x and later both _M_refcount and _M_length
+ // are initialized in the callers, unfortunately we can
+ // have 3.4.x compiled code with _S_create callers inlined
+ // calling 4.0.x+ _S_create.
+ __p->_M_set_sharable();
+ return __p;
+ }
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ _CharT*
+ basic_string<_CharT, _Traits, _Alloc>::_Rep::
+ _M_clone(const _Alloc& __alloc, size_type __res)
+ {
+ // Requested capacity of the clone.
+ const size_type __requested_cap = this->_M_length + __res;
+ _Rep* __r = _Rep::_S_create(__requested_cap, this->_M_capacity,
+ __alloc);
+ if (this->_M_length)
+ _M_copy(__r->_M_refdata(), _M_refdata(), this->_M_length);
+
+ __r->_M_set_length_and_sharable(this->_M_length);
+ return __r->_M_refdata();
+ }
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ void
+ basic_string<_CharT, _Traits, _Alloc>::
+ resize(size_type __n, _CharT __c)
+ {
+ const size_type __size = this->size();
+ _M_check_length(__size, __n, "basic_string::resize");
+ if (__size < __n)
+ this->append(__n - __size, __c);
+ else if (__n < __size)
+ this->erase(__n);
+ // else nothing (in particular, avoid calling _M_mutate() unnecessarily.)
+ }
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ template<typename _InputIterator>
+ basic_string<_CharT, _Traits, _Alloc>&
+ basic_string<_CharT, _Traits, _Alloc>::
+ _M_replace_dispatch(iterator __i1, iterator __i2, _InputIterator __k1,
+ _InputIterator __k2, __false_type)
+ {
+ const basic_string __s(__k1, __k2);
+ const size_type __n1 = __i2 - __i1;
+ _M_check_length(__n1, __s.size(), "basic_string::_M_replace_dispatch");
+ return _M_replace_safe(__i1 - _M_ibegin(), __n1, __s._M_data(),
+ __s.size());
+ }
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ basic_string<_CharT, _Traits, _Alloc>&
+ basic_string<_CharT, _Traits, _Alloc>::
+ _M_replace_aux(size_type __pos1, size_type __n1, size_type __n2,
+ _CharT __c)
+ {
+ _M_check_length(__n1, __n2, "basic_string::_M_replace_aux");
+ _M_mutate(__pos1, __n1, __n2);
+ if (__n2)
+ _M_assign(_M_data() + __pos1, __n2, __c);
+ return *this;
+ }
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ basic_string<_CharT, _Traits, _Alloc>&
+ basic_string<_CharT, _Traits, _Alloc>::
+ _M_replace_safe(size_type __pos1, size_type __n1, const _CharT* __s,
+ size_type __n2)
+ {
+ _M_mutate(__pos1, __n1, __n2);
+ if (__n2)
+ _M_copy(_M_data() + __pos1, __s, __n2);
+ return *this;
+ }
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ void
+ basic_string<_CharT, _Traits, _Alloc>::
+ reserve()
+ {
+#if __cpp_exceptions
+ if (length() < capacity() || _M_rep()->_M_is_shared())
+ try
+ {
+ const allocator_type __a = get_allocator();
+ _CharT* __tmp = _M_rep()->_M_clone(__a);
+ _M_rep()->_M_dispose(__a);
+ _M_data(__tmp);
+ }
+ catch (const __cxxabiv1::__forced_unwind&)
+ { throw; }
+ catch (...)
+ { /* swallow the exception */ }
+#endif
+ }
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
+ typename basic_string<_CharT, _Traits, _Alloc>::size_type
+ basic_string<_CharT, _Traits, _Alloc>::
+ copy(_CharT* __s, size_type __n, size_type __pos) const
+ {
+ _M_check(__pos, "basic_string::copy");
+ __n = _M_limit(__pos, __n);
+ __glibcxx_requires_string_len(__s, __n);
+ if (__n)
+ _M_copy(__s, _M_data() + __pos, __n);
+ // 21.3.5.7 par 3: do not append null. (good.)
+ return __n;
+ }
+_GLIBCXX_END_NAMESPACE_VERSION
+} // namespace std
+#endif // ! _GLIBCXX_USE_CXX11_ABI
+#endif // _COW_STRING_H