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Diffstat (limited to 'boost/vmd/tuple/pop_back.hpp')
-rw-r--r-- | boost/vmd/tuple/pop_back.hpp | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/boost/vmd/tuple/pop_back.hpp b/boost/vmd/tuple/pop_back.hpp new file mode 100644 index 0000000000..e9a7558969 --- /dev/null +++ b/boost/vmd/tuple/pop_back.hpp @@ -0,0 +1,73 @@ + +// (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_TUPLE_POP_BACK_HPP) +#define BOOST_VMD_TUPLE_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/tuple/pop_back.hpp> +#include <boost/preprocessor/tuple/size.hpp> +#include <boost/vmd/empty.hpp> + +/* + + The succeeding comments in this file are in doxygen format. + +*/ + +/** \file +*/ + +/** \def BOOST_VMD_TUPLE_POP_BACK(tuple) + + \brief pops an element from the end of a tuple. + + tuple = tuple to pop an element from. + + If the tuple is an empty tuple the result is undefined. + If the tuple is a single element the result is an empty tuple. + Otherwise the result is a tuple after removing the last element. +*/ + +#define BOOST_VMD_TUPLE_POP_BACK(tuple) \ + BOOST_PP_IIF \ + ( \ + BOOST_PP_EQUAL(BOOST_PP_TUPLE_SIZE(tuple),1), \ + BOOST_VMD_EMPTY, \ + BOOST_PP_TUPLE_POP_BACK \ + ) \ + (tuple) \ +/**/ + +/** \def BOOST_VMD_TUPLE_POP_BACK_Z(z,tuple) + + \brief pops an element from the end of a tuple. It reenters BOOST_PP_REPEAT with maximum efficiency. + + z = the next available BOOST_PP_REPEAT dimension. + tuple = tuple to pop an element from. + + If the tuple is an empty tuple the result is undefined. + If the tuple is a single element the result is an empty tuple. + Otherwise the result is a tuple after removing the last element. +*/ + +#define BOOST_VMD_TUPLE_POP_BACK_Z(z,tuple) \ + BOOST_PP_IIF \ + ( \ + BOOST_PP_EQUAL(BOOST_PP_TUPLE_SIZE(tuple),1), \ + BOOST_VMD_EMPTY, \ + BOOST_PP_TUPLE_POP_BACK_Z \ + ) \ + (z,tuple) \ +/**/ + +#endif /* BOOST_PP_VARIADICS */ +#endif /* BOOST_VMD_TUPLE_POP_BACK_HPP */ |