axmol/thirdparty/range-v3/include/range/v3/range_for.hpp

51 lines
2.4 KiB
C++

/// \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