[/
    Copyright 2010 Neil Groves
    Distributed under the Boost Software License, Version 1.0.
    (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
/]
[section:upgrade Upgrade version of Boost.Range]

[section:upgrade_from_1_55 Upgrade from version 1.55]
# __iterator_range__ is now implemented by implementing the member functions
`size()`, `operator[]` via inheritance of base-classes specialized by the
traversal type of the underlying iterator. This is normally requires no
alteration of code. It does mean that types that derive from iterator_range may
need to prefix `this->` to the various member functions. Additionally it has
been noted that some calling code was relying on member functions such as
`size()` being present despite the underlying iterators not being random-access
due to `iterator_reference<Iter>::type` not being a reference. The suggested
refactoring is to use `boost::size(rng)`.
# The undocumented __iterator_range__ `pop_front()` has been deprecated and is
replaced by `drop_front(). Similarly `pop_back()` has been replaced by
`drop_back()`.

[endsect]

[section:upgrade_from_1_49 Upgrade from version 1.49]

# __size__ now returns the type Rng::size_type if the range has size_type;
otherwise range_size<Rng>::type is used. This is the distance type promoted to
an unsigned type.

[endsect]

[section:upgrade_from_1_45 Upgrade from version 1.45]

# __size__ in addition to supporting __random_access_range__ now also supports extensibility via calls to the unqualified `range_calculate_size(rng)` function.
# __range_adaptors_strided__ now in addition to working with any RandomAccessRange additionally works for any SinglePassRange for which `boost::size(rng)` is valid.
# __range_adaptors_strided__ no longer requires `distance(rng) % stride_size == 0` or `stride_size < distance(rng)`

[endsect]

[section:upgrade_from_1_42 Upgrade from version 1.42]

New features:

# __range_adaptors__
# __range_algorithms__

Removed:

# `iterator_range` no longer has a `is_singular` member function. The singularity restrictions have been removed from the `iterator_range` class since this added restrictions to ranges of iterators whose default constructors were not singular. Previously the `is_singular` member function always returned `false` in release build configurations, hence it is not anticipated that this interface change will produce difficulty in upgrading.


[endsect]

[section:upgrade_from_1_34 Upgrade from version 1.34]

Boost version 1.35 introduced some larger refactorings of the library:

# Direct support for character arrays was abandoned in favor of uniform treatment of all arrays. Instead string algorithms can use the new function __as_literal__`()`.
# __size__ now requires a __random_access_range__. The old behavior is provided as __distance__`()`.
# `range_size<T>::type` has been completely removed in favor of `range_difference<T>::type`
# `boost_range_begin()` and `boost_range_end()` have been renamed `range_begin()` and `range_end()` respectively.
# `range_result_iterator<T>::type` and `range_reverse_result_iterator<T>::type` have been renamed `range_iterator<T>::type` and `range_reverse_iterator<T>::type`.
# The procedure that makes a custom type work with the library has been greatly simplified. See __extending_for_udts__ for details.

[endsect]

[endsect]