ecency-mobile/ios/Pods/boost-for-react-native/boost/lambda/casts.hpp

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5.7 KiB
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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