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- /// \file
- // Range v3 library
- //
- // Copyright Eric Niebler 2014-present
- //
- // Use, modification and distribution is subject to 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)
- //
- // Project home: https://github.com/ericniebler/range-v3
- //
-
- #ifndef RANGES_V3_RANGE_FOR_HPP
- #define RANGES_V3_RANGE_FOR_HPP
-
- #include <range/v3/range_fwd.hpp>
-
- #include <range/v3/range/access.hpp>
-
- #if RANGES_CXX_RANGE_BASED_FOR < RANGES_CXX_RANGE_BASED_FOR_17
- /// A range-based for macro, basically a hack until the built-in range-for can handle
- /// Ranges that have a different type for begin and end. \ingroup range-core
- #define RANGES_FOR(VAR_DECL, ...) \
- if(bool CPP_PP_CAT(_range_v3_done, __LINE__) = false) {} \
- else \
- for(auto && CPP_PP_CAT(_range_v3_rng, __LINE__) = (__VA_ARGS__); \
- !CPP_PP_CAT(_range_v3_done, __LINE__);) \
- for(auto CPP_PP_CAT(_range_v3_begin, __LINE__) = \
- ranges::begin(CPP_PP_CAT(_range_v3_rng, __LINE__)); \
- !CPP_PP_CAT(_range_v3_done, __LINE__); \
- CPP_PP_CAT(_range_v3_done, __LINE__) = true) \
- for(auto CPP_PP_CAT(_range_v3_end, __LINE__) = \
- ranges::end(CPP_PP_CAT(_range_v3_rng, __LINE__)); \
- !CPP_PP_CAT(_range_v3_done, __LINE__) && \
- CPP_PP_CAT(_range_v3_begin, __LINE__) != \
- CPP_PP_CAT(_range_v3_end, __LINE__); \
- ++CPP_PP_CAT(_range_v3_begin, __LINE__)) \
- if(!(CPP_PP_CAT(_range_v3_done, __LINE__) = true)) {} \
- else \
- for(VAR_DECL = *CPP_PP_CAT(_range_v3_begin, __LINE__); \
- CPP_PP_CAT(_range_v3_done, __LINE__); \
- CPP_PP_CAT(_range_v3_done, __LINE__) = false) \
- /**/
-
- #else
- #define RANGES_FOR(VAR_DECL, ...) for(VAR_DECL : (__VA_ARGS__))
- #endif
-
- #endif
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