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Diffstat (limited to 'boost/vmd/seq/pop_back.hpp')
| -rw-r--r-- | boost/vmd/seq/pop_back.hpp | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/boost/vmd/seq/pop_back.hpp b/boost/vmd/seq/pop_back.hpp new file mode 100644 index 0000000000..5e3865a552 --- /dev/null +++ b/boost/vmd/seq/pop_back.hpp @@ -0,0 +1,51 @@ + +// (C) Copyright Edward Diener 2015 +// Use, modification and distribution are 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). + +#if !defined(BOOST_VMD_SEQ_POP_BACK_HPP) +#define BOOST_VMD_SEQ_POP_BACK_HPP + +#include <boost/vmd/detail/setup.hpp> + +#if BOOST_PP_VARIADICS + +#include <boost/preprocessor/comparison/equal.hpp> +#include <boost/preprocessor/control/iif.hpp> +#include <boost/preprocessor/seq/pop_back.hpp> +#include <boost/preprocessor/seq/size.hpp> +#include <boost/vmd/empty.hpp> + +/* + + The succeeding comments in this file are in doxygen format. + +*/ + +/** \file +*/ + +/** \def BOOST_VMD_SEQ_POP_BACK(seq) + + \brief pops an element from the end of a seq. + + seq = seq to pop an element from. + + If the seq is an empty seq the result is undefined. + If the seq is a single element the result is an empty seq. + Otherwise the result is a seq after removing the last element. +*/ + +#define BOOST_VMD_SEQ_POP_BACK(seq) \ + BOOST_PP_IIF \ + ( \ + BOOST_PP_EQUAL(BOOST_PP_SEQ_SIZE(seq),1), \ + BOOST_VMD_EMPTY, \ + BOOST_PP_SEQ_POP_BACK \ + ) \ + (seq) \ +/**/ + +#endif /* BOOST_PP_VARIADICS */ +#endif /* BOOST_VMD_SEQ_POP_BACK_HPP */ |