libs/scope_exit/test/same_line.cpp

   1
   2 // Copyright (C) 2006-2009, 2012 Alexander Nasonov
   3 // Copyright (C) 2012 Lorenzo Caminiti
   4 // Distributed under the Boost Software License, Version 1.0
   5 // (see accompanying file LICENSE_1_0.txt or a copy at
   6 // http://www.boost.org/LICENSE_1_0.txt)
   7 // Home at http://www.boost.org/libs/scope_exit
   8
   9 #include <boost/config.hpp>
  10 #ifdef BOOST_NO_VARIADIC_MACROS
  11 #   error "variadic macros required"
  12 #else
  13
  14 #include <boost/scope_exit.hpp>
  15 #include <boost/preprocessor/cat.hpp>
  16 #include <boost/detail/lightweight_test.hpp>
  17
  18 //[same_line
  19 #define SCOPE_EXIT_INC_DEC(variable, offset) \
  20     BOOST_SCOPE_EXIT_ID(BOOST_PP_CAT(inc, __LINE__), /* unique ID */ \
  21             &variable, offset) { \
  22         variable += offset; \
  23     } BOOST_SCOPE_EXIT_END_ID(BOOST_PP_CAT(inc, __LINE__)) \
  24     \
  25     BOOST_SCOPE_EXIT_ID(BOOST_PP_CAT(dec, __LINE__), \
  26             &variable, offset) { \
  27         variable -= offset; \
  28     } BOOST_SCOPE_EXIT_END_ID(BOOST_PP_CAT(dec, __LINE__))
  29
  30 #define SCOPE_EXIT_INC_DEC_TPL(variable, offset) \
  31     BOOST_SCOPE_EXIT_ID_TPL(BOOST_PP_CAT(inc, __LINE__), \
  32             &variable, offset) { \
  33         variable += offset; \
  34     } BOOST_SCOPE_EXIT_END_ID(BOOST_PP_CAT(inc, __LINE__)) \
  35     \
  36     BOOST_SCOPE_EXIT_ID_TPL(BOOST_PP_CAT(dec, __LINE__), \
  37             &variable, offset) { \
  38         variable -= offset; \
  39     } BOOST_SCOPE_EXIT_END_ID(BOOST_PP_CAT(dec, __LINE__))
  40
  41 #define SCOPE_EXIT_ALL_INC_DEC(variable, offset) \
  42     BOOST_SCOPE_EXIT_ALL_ID(BOOST_PP_CAT(inc, __LINE__), \
  43             =, &variable) { \
  44         variable += offset; \
  45     }; \
  46     BOOST_SCOPE_EXIT_ALL_ID(BOOST_PP_CAT(dec, __LINE__), \
  47             =, &variable) { \
  48         variable -= offset; \
  49     };
  50
  51 template<typename T>
  52 void f(T& x, T& delta) {
  53     SCOPE_EXIT_INC_DEC_TPL(x, delta) // Multiple scope exits on same line.
  54     BOOST_TEST(x == 0);
  55 }
  56
  57 int main(void) {
  58     int x = 0, delta = 10;
  59
  60     {
  61         SCOPE_EXIT_INC_DEC(x, delta) // Multiple scope exits on same line.
  62     }
  63     BOOST_TEST(x == 0);
  64
  65     f(x, delta);
  66
  67 #ifndef BOOST_NO_LAMBDAS
  68     {
  69         SCOPE_EXIT_ALL_INC_DEC(x, delta) // Multiple scope exits on same line.
  70     }
  71     BOOST_TEST(x == 0);
  72 #endif // LAMBDAS
  73
  74     return boost::report_errors();
  75 }
  76 //]
  77
  78 #endif // variadic macros
  79