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- // - casts.hpp -- BLambda Library -------------
- //
- // Copyright (C) 2000 Gary Powell (powellg@amazon.com)
- // Copyright (C) 1999, 2000 Jaakko Jarvi (jaakko.jarvi@cs.utu.fi)
- //
- // 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)
- //
- // For more information, see http://www.boost.org
- // -----------------------------------------------
- #if !defined(BOOST_LAMBDA_CASTS_HPP)
- #define BOOST_LAMBDA_CASTS_HPP
- #include "boost/lambda/detail/suppress_unused.hpp"
- #include "boost/lambda/core.hpp"
- #include <typeinfo>
- namespace boost {
- namespace lambda {
- template<class Act, class Args>
- struct return_type_N;
- template<class T> class cast_action;
- template<class T> class static_cast_action;
- template<class T> class dynamic_cast_action;
- template<class T> class const_cast_action;
- template<class T> class reinterpret_cast_action;
- class typeid_action;
- class sizeof_action;
- // Cast actions
- template<class T> class cast_action<static_cast_action<T> >
- {
- public:
- template<class RET, class Arg1>
- static RET apply(Arg1 &a1) {
- return static_cast<RET>(a1);
- }
- };
- template<class T> class cast_action<dynamic_cast_action<T> > {
- public:
- template<class RET, class Arg1>
- static RET apply(Arg1 &a1) {
- return dynamic_cast<RET>(a1);
- }
- };
- template<class T> class cast_action<const_cast_action<T> > {
- public:
- template<class RET, class Arg1>
- static RET apply(Arg1 &a1) {
- return const_cast<RET>(a1);
- }
- };
- template<class T> class cast_action<reinterpret_cast_action<T> > {
- public:
- template<class RET, class Arg1>
- static RET apply(Arg1 &a1) {
- return reinterpret_cast<RET>(a1);
- }
- };
- // typeid action
- class typeid_action {
- public:
- template<class RET, class Arg1>
- static RET apply(Arg1 &a1) {
- detail::suppress_unused_variable_warnings(a1);
- return typeid(a1);
- }
- };
- // sizeof action
- class sizeof_action
- {
- public:
- template<class RET, class Arg1>
- static RET apply(Arg1 &a1) {
- return sizeof(a1);
- }
- };
- // return types of casting lambda_functors (all "T" type.)
- template<template <class> class cast_type, class T, class A>
- struct return_type_N<cast_action< cast_type<T> >, A> {
- typedef T type;
- };
- // return type of typeid_action
- template<class A>
- struct return_type_N<typeid_action, A> {
- typedef std::type_info const & type;
- };
- // return type of sizeof_action
- template<class A>
- struct return_type_N<sizeof_action, A> {
- typedef std::size_t type;
- };
- // the four cast & typeid overloads.
- // casts can take ordinary variables (not just lambda functors)
- // static_cast
- template <class T, class Arg1>
- inline const lambda_functor<
- lambda_functor_base<
- action<1, cast_action<static_cast_action<T> > >,
- tuple<typename const_copy_argument <const Arg1>::type>
- >
- >
- ll_static_cast(const Arg1& a1) {
- return
- lambda_functor_base<
- action<1, cast_action<static_cast_action<T> > >,
- tuple<typename const_copy_argument <const Arg1>::type>
- >
- ( tuple<typename const_copy_argument <const Arg1>::type>(a1));
- }
- // dynamic_cast
- template <class T, class Arg1>
- inline const lambda_functor<
- lambda_functor_base<
- action<1, cast_action<dynamic_cast_action<T> > >,
- tuple<typename const_copy_argument <const Arg1>::type>
- >
- >
- ll_dynamic_cast(const Arg1& a1) {
- return
- lambda_functor_base<
- action<1, cast_action<dynamic_cast_action<T> > >,
- tuple<typename const_copy_argument <const Arg1>::type>
- >
- ( tuple<typename const_copy_argument <const Arg1>::type>(a1));
- }
- // const_cast
- template <class T, class Arg1>
- inline const lambda_functor<
- lambda_functor_base<
- action<1, cast_action<const_cast_action<T> > >,
- tuple<typename const_copy_argument <const Arg1>::type>
- >
- >
- ll_const_cast(const Arg1& a1) {
- return
- lambda_functor_base<
- action<1, cast_action<const_cast_action<T> > >,
- tuple<typename const_copy_argument <const Arg1>::type>
- >
- ( tuple<typename const_copy_argument <const Arg1>::type>(a1));
- }
- // reinterpret_cast
- template <class T, class Arg1>
- inline const lambda_functor<
- lambda_functor_base<
- action<1, cast_action<reinterpret_cast_action<T> > >,
- tuple<typename const_copy_argument <const Arg1>::type>
- >
- >
- ll_reinterpret_cast(const Arg1& a1) {
- return
- lambda_functor_base<
- action<1, cast_action<reinterpret_cast_action<T> > >,
- tuple<typename const_copy_argument <const Arg1>::type>
- >
- ( tuple<typename const_copy_argument <const Arg1>::type>(a1));
- }
- // typeid
- // can be applied to a normal variable as well (can refer to a polymorphic
- // class object)
- template <class Arg1>
- inline const lambda_functor<
- lambda_functor_base<
- action<1, typeid_action>,
- tuple<typename const_copy_argument <const Arg1>::type>
- >
- >
- ll_typeid(const Arg1& a1) {
- return
- lambda_functor_base<
- action<1, typeid_action>,
- tuple<typename const_copy_argument <const Arg1>::type>
- >
- ( tuple<typename const_copy_argument <const Arg1>::type>(a1));
- }
- // sizeof(expression)
- // Always takes a lambda expression (if not, built in sizeof will do)
- template <class Arg1>
- inline const lambda_functor<
- lambda_functor_base<
- action<1, sizeof_action>,
- tuple<lambda_functor<Arg1> >
- >
- >
- ll_sizeof(const lambda_functor<Arg1>& a1) {
- return
- lambda_functor_base<
- action<1, sizeof_action>,
- tuple<lambda_functor<Arg1> >
- >
- ( tuple<lambda_functor<Arg1> >(a1));
- }
- } // namespace lambda
- } // namespace boost
- #endif
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