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Diffstat (limited to '3rdParty/Boost/src/boost/proto/context/null.hpp')
-rw-r--r-- | 3rdParty/Boost/src/boost/proto/context/null.hpp | 56 |
1 files changed, 56 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..7e0dc5f --- /dev/null +++ b/3rdParty/Boost/src/boost/proto/context/null.hpp @@ -0,0 +1,56 @@ +/////////////////////////////////////////////////////////////////////////////// +/// \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 + {} + }; + + // Additional specializations generated by the preprocessor + #include <boost/proto/context/detail/null_eval.hpp> + + /// null_context + /// + struct null_context + { + /// null_context::eval + /// + template<typename Expr, typename ThisContext = null_context const> + struct eval + : null_eval<Expr, ThisContext> + {}; + }; + +}}} + +#endif |