diff options
Diffstat (limited to '3rdParty/Boost/src/boost/proto/context/null.hpp')
-rw-r--r-- | 3rdParty/Boost/src/boost/proto/context/null.hpp | 85 |
1 files changed, 85 insertions, 0 deletions
diff --git a/3rdParty/Boost/src/boost/proto/context/null.hpp b/3rdParty/Boost/src/boost/proto/context/null.hpp new file mode 100644 index 0000000..4906578 --- /dev/null +++ b/3rdParty/Boost/src/boost/proto/context/null.hpp @@ -0,0 +1,85 @@ +#ifndef BOOST_PP_IS_ITERATING + /////////////////////////////////////////////////////////////////////////////// + /// \file null.hpp + /// Definintion of null_context\<\>, an evaluation context for + /// proto::eval() that simply evaluates each child expression, doesn't + /// combine the results at all, and returns void. + // + // Copyright 2008 Eric Niebler. Distributed under 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) + + #ifndef BOOST_PROTO_CONTEXT_NULL_HPP_EAN_06_24_2007 + #define BOOST_PROTO_CONTEXT_NULL_HPP_EAN_06_24_2007 + + #include <boost/preprocessor/iteration/iterate.hpp> + #include <boost/preprocessor/repetition/repeat.hpp> + #include <boost/proto/proto_fwd.hpp> + #include <boost/proto/eval.hpp> + #include <boost/proto/traits.hpp> + + namespace boost { namespace proto { namespace context + { + + template< + typename Expr + , typename Context + , long Arity // = Expr::proto_arity_c + > + struct null_eval + {}; + + template<typename Expr, typename Context> + struct null_eval<Expr, Context, 0> + { + typedef void result_type; + void operator()(Expr &, Context &) const + {} + }; + + #define BOOST_PROTO_EVAL_N(Z, N, DATA) \ + proto::eval(proto::child_c<N>(expr), ctx); \ + /**/ + + #define BOOST_PP_ITERATION_PARAMS_1 \ + (3, (1, BOOST_PROTO_MAX_ARITY, <boost/proto/context/null.hpp>)) \ + /**/ + + #include BOOST_PP_ITERATE() + + #undef BOOST_PROTO_EVAL_N + + /// null_context + /// + struct null_context + { + /// null_context::eval + /// + template<typename Expr, typename ThisContext = null_context const> + struct eval + : null_eval<Expr, ThisContext> + {}; + }; + + }}} + + #endif + +#else + + #define N BOOST_PP_ITERATION() + + template<typename Expr, typename Context> + struct null_eval<Expr, Context, N> + { + typedef void result_type; + + void operator ()(Expr &expr, Context &ctx) const + { + BOOST_PP_REPEAT(N, BOOST_PROTO_EVAL_N, ~) + } + }; + + #undef N + +#endif |