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Diffstat (limited to '3rdParty/Boost/src/boost/proto/transform/lazy.hpp')
-rw-r--r-- | 3rdParty/Boost/src/boost/proto/transform/lazy.hpp | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/3rdParty/Boost/src/boost/proto/transform/lazy.hpp b/3rdParty/Boost/src/boost/proto/transform/lazy.hpp new file mode 100644 index 0000000..09581a9 --- /dev/null +++ b/3rdParty/Boost/src/boost/proto/transform/lazy.hpp @@ -0,0 +1,83 @@ +#ifndef BOOST_PP_IS_ITERATING + /////////////////////////////////////////////////////////////////////////////// + /// \file lazy.hpp + /// Contains definition of the lazy<> transform. + // + // 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_TRANSFORM_LAZY_HPP_EAN_12_02_2007 + #define BOOST_PROTO_TRANSFORM_LAZY_HPP_EAN_12_02_2007 + + #include <boost/preprocessor/iteration/iterate.hpp> + #include <boost/preprocessor/repetition/enum_params.hpp> + #include <boost/preprocessor/repetition/enum_trailing_params.hpp> + #include <boost/proto/proto_fwd.hpp> + #include <boost/proto/transform/make.hpp> + #include <boost/proto/transform/call.hpp> + #include <boost/proto/transform/impl.hpp> + + namespace boost { namespace proto + { + /// \brief A PrimitiveTransform that uses <tt>make\<\></tt> to build + /// a CallableTransform, and then uses <tt>call\<\></tt> to apply it. + /// + /// <tt>lazy\<\></tt> is useful as a higher-order transform, when the + /// transform to be applied depends on the current state of the + /// transformation. The invocation of the <tt>make\<\></tt> transform + /// evaluates any nested transforms, and the resulting type is treated + /// as a CallableTransform, which is evaluated with <tt>call\<\></tt>. + template<typename Object> + struct lazy : transform<lazy<Object> > + { + template<typename Expr, typename State, typename Data> + struct impl + : call< + typename make<Object>::template impl<Expr, State, Data>::result_type + >::template impl<Expr, State, Data> + {}; + }; + + #define BOOST_PP_ITERATION_PARAMS_1 (3, (0, BOOST_PROTO_MAX_ARITY, <boost/proto/transform/lazy.hpp>)) + #include BOOST_PP_ITERATE() + + /// INTERNAL ONLY + /// + template<typename Object> + struct is_callable<lazy<Object> > + : mpl::true_ + {}; + + }} + + #endif + +#else + + #define N BOOST_PP_ITERATION() + + /// \brief A PrimitiveTransform that uses <tt>make\<\></tt> to build + /// a CallableTransform, and then uses <tt>call\<\></tt> to apply it. + /// + /// <tt>lazy\<\></tt> is useful as a higher-order transform, when the + /// transform to be applied depends on the current state of the + /// transformation. The invocation of the <tt>make\<\></tt> transform + /// evaluates any nested transforms, and the resulting type is treated + /// as a CallableTransform, which is evaluated with <tt>call\<\></tt>. + template<typename Object BOOST_PP_ENUM_TRAILING_PARAMS(N, typename A)> + struct lazy<Object(BOOST_PP_ENUM_PARAMS(N, A))> + : transform<lazy<Object(BOOST_PP_ENUM_PARAMS(N, A))> > + { + template<typename Expr, typename State, typename Data> + struct impl + : call< + typename make<Object>::template impl<Expr, State, Data>::result_type + (BOOST_PP_ENUM_PARAMS(N, A)) + >::template impl<Expr, State, Data> + {}; + }; + + #undef N + +#endif |