You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and dots ('.'), can be up to 35 characters long. Letters must be lowercase.
324 lines
9.9 KiB
324 lines
9.9 KiB
// Boost Lambda Library - lambda_functors.hpp ------------------------------- |
|
|
|
// 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 |
|
|
|
// ------------------------------------------------ |
|
|
|
#ifndef BOOST_LAMBDA_LAMBDA_FUNCTORS_HPP |
|
#define BOOST_LAMBDA_LAMBDA_FUNCTORS_HPP |
|
|
|
#include <boost/config.hpp> |
|
#include <boost/detail/workaround.hpp> |
|
|
|
#if BOOST_WORKAROUND(BOOST_MSVC, == 1310) |
|
|
|
#include <boost/mpl/or.hpp> |
|
#include <boost/utility/enable_if.hpp> |
|
#include <boost/type_traits/is_array.hpp> |
|
|
|
#define BOOST_LAMBDA_DISABLE_IF_ARRAY1(A1, R1)\ |
|
typename lazy_disable_if<is_array<A1>, typename R1 >::type |
|
#define BOOST_LAMBDA_DISABLE_IF_ARRAY2(A1, A2, R1, R2) \ |
|
typename lazy_disable_if<mpl::or_<is_array<A1>, is_array<A2> >, typename R1, R2 >::type |
|
#define BOOST_LAMBDA_DISABLE_IF_ARRAY3(A1, A2, A3, R1, R2, R3) \ |
|
typename lazy_disable_if<mpl::or_<is_array<A1>, is_array<A2>, is_array<A3> >, typename R1, R2, R3 >::type |
|
|
|
#else |
|
|
|
#define BOOST_LAMBDA_DISABLE_IF_ARRAY1(A1, R1) typename R1::type |
|
#define BOOST_LAMBDA_DISABLE_IF_ARRAY2(A1, A2, R1, R2) typename R1, R2::type |
|
#define BOOST_LAMBDA_DISABLE_IF_ARRAY3(A1, A2, A3, R1, R2, R3) typename R1, R2, R3::type |
|
|
|
#endif |
|
|
|
namespace boost { |
|
namespace lambda { |
|
|
|
// -- lambda_functor -------------------------------------------- |
|
// -------------------------------------------------------------- |
|
|
|
//inline const null_type const_null_type() { return null_type(); } |
|
|
|
namespace detail { |
|
namespace { |
|
|
|
static const null_type constant_null_type = null_type(); |
|
|
|
} // unnamed |
|
} // detail |
|
|
|
class unused {}; |
|
|
|
#define cnull_type() detail::constant_null_type |
|
|
|
// -- free variables types -------------------------------------------------- |
|
|
|
// helper to work around the case where the nullary return type deduction |
|
// is always performed, even though the functor is not nullary |
|
namespace detail { |
|
template<int N, class Tuple> struct get_element_or_null_type { |
|
typedef typename |
|
detail::tuple_element_as_reference<N, Tuple>::type type; |
|
}; |
|
template<int N> struct get_element_or_null_type<N, null_type> { |
|
typedef null_type type; |
|
}; |
|
} |
|
|
|
template <int I> struct placeholder; |
|
|
|
template<> struct placeholder<FIRST> { |
|
|
|
template<class SigArgs> struct sig { |
|
typedef typename detail::get_element_or_null_type<0, SigArgs>::type type; |
|
}; |
|
|
|
template<class RET, CALL_TEMPLATE_ARGS> |
|
RET call(CALL_FORMAL_ARGS) const { |
|
BOOST_STATIC_ASSERT(boost::is_reference<RET>::value); |
|
CALL_USE_ARGS; // does nothing, prevents warnings for unused args |
|
return a; |
|
} |
|
}; |
|
|
|
template<> struct placeholder<SECOND> { |
|
|
|
template<class SigArgs> struct sig { |
|
typedef typename detail::get_element_or_null_type<1, SigArgs>::type type; |
|
}; |
|
|
|
template<class RET, CALL_TEMPLATE_ARGS> |
|
RET call(CALL_FORMAL_ARGS) const { CALL_USE_ARGS; return b; } |
|
}; |
|
|
|
template<> struct placeholder<THIRD> { |
|
|
|
template<class SigArgs> struct sig { |
|
typedef typename detail::get_element_or_null_type<2, SigArgs>::type type; |
|
}; |
|
|
|
template<class RET, CALL_TEMPLATE_ARGS> |
|
RET call(CALL_FORMAL_ARGS) const { CALL_USE_ARGS; return c; } |
|
}; |
|
|
|
template<> struct placeholder<EXCEPTION> { |
|
|
|
template<class SigArgs> struct sig { |
|
typedef typename detail::get_element_or_null_type<3, SigArgs>::type type; |
|
}; |
|
|
|
template<class RET, CALL_TEMPLATE_ARGS> |
|
RET call(CALL_FORMAL_ARGS) const { CALL_USE_ARGS; return env; } |
|
}; |
|
|
|
typedef const lambda_functor<placeholder<FIRST> > placeholder1_type; |
|
typedef const lambda_functor<placeholder<SECOND> > placeholder2_type; |
|
typedef const lambda_functor<placeholder<THIRD> > placeholder3_type; |
|
|
|
|
|
/////////////////////////////////////////////////////////////////////////////// |
|
|
|
|
|
// free variables are lambda_functors. This is to allow uniform handling with |
|
// other lambda_functors. |
|
// ------------------------------------------------------------------- |
|
|
|
#if BOOST_WORKAROUND(BOOST_MSVC, >= 1400) |
|
#pragma warning(push) |
|
#pragma warning(disable:4512) //assignment operator could not be generated |
|
#endif |
|
|
|
// -- lambda_functor NONE ------------------------------------------------ |
|
template <class T> |
|
class lambda_functor : public T |
|
{ |
|
|
|
BOOST_STATIC_CONSTANT(int, arity_bits = get_arity<T>::value); |
|
|
|
public: |
|
typedef T inherited; |
|
|
|
lambda_functor() {} |
|
lambda_functor(const lambda_functor& l) : inherited(l) {} |
|
|
|
lambda_functor(const T& t) : inherited(t) {} |
|
|
|
template <class SigArgs> struct sig { |
|
typedef typename inherited::template |
|
sig<typename SigArgs::tail_type>::type type; |
|
}; |
|
|
|
// Note that this return type deduction template is instantiated, even |
|
// if the nullary |
|
// operator() is not called at all. One must make sure that it does not fail. |
|
typedef typename |
|
inherited::template sig<null_type>::type |
|
nullary_return_type; |
|
|
|
// Support for boost::result_of. |
|
template <class Sig> struct result; |
|
template <class F> |
|
struct result<F()> { |
|
typedef nullary_return_type type; |
|
}; |
|
template <class F, class A> |
|
struct result<F(A)> { |
|
typedef typename sig<tuple<F, A> >::type type; |
|
}; |
|
template <class F, class A, class B> |
|
struct result<F(A, B)> { |
|
typedef typename sig<tuple<F, A, B> >::type type; |
|
}; |
|
template <class F, class A, class B, class C> |
|
struct result<F(A, B, C)> { |
|
typedef typename sig<tuple<F, A, B, C> >::type type; |
|
}; |
|
|
|
nullary_return_type operator()() const { |
|
return inherited::template |
|
call<nullary_return_type> |
|
(cnull_type(), cnull_type(), cnull_type(), cnull_type()); |
|
} |
|
|
|
template<class A> |
|
typename inherited::template sig<tuple<A&> >::type |
|
operator()(A& a) const { |
|
return inherited::template call< |
|
typename inherited::template sig<tuple<A&> >::type |
|
>(a, cnull_type(), cnull_type(), cnull_type()); |
|
} |
|
|
|
template<class A> |
|
BOOST_LAMBDA_DISABLE_IF_ARRAY1(A, inherited::template sig<tuple<A const&> >) |
|
operator()(A const& a) const { |
|
return inherited::template call< |
|
typename inherited::template sig<tuple<A const&> >::type |
|
>(a, cnull_type(), cnull_type(), cnull_type()); |
|
} |
|
|
|
template<class A, class B> |
|
typename inherited::template sig<tuple<A&, B&> >::type |
|
operator()(A& a, B& b) const { |
|
return inherited::template call< |
|
typename inherited::template sig<tuple<A&, B&> >::type |
|
>(a, b, cnull_type(), cnull_type()); |
|
} |
|
|
|
template<class A, class B> |
|
BOOST_LAMBDA_DISABLE_IF_ARRAY2(A, B, inherited::template sig<tuple<A const&, B&> >) |
|
operator()(A const& a, B& b) const { |
|
return inherited::template call< |
|
typename inherited::template sig<tuple<A const&, B&> >::type |
|
>(a, b, cnull_type(), cnull_type()); |
|
} |
|
|
|
template<class A, class B> |
|
BOOST_LAMBDA_DISABLE_IF_ARRAY2(A, B, inherited::template sig<tuple<A&, B const&> >) |
|
operator()(A& a, B const& b) const { |
|
return inherited::template call< |
|
typename inherited::template sig<tuple<A&, B const&> >::type |
|
>(a, b, cnull_type(), cnull_type()); |
|
} |
|
|
|
template<class A, class B> |
|
BOOST_LAMBDA_DISABLE_IF_ARRAY2(A, B, inherited::template sig<tuple<A const&, B const&> >) |
|
operator()(A const& a, B const& b) const { |
|
return inherited::template call< |
|
typename inherited::template sig<tuple<A const&, B const&> >::type |
|
>(a, b, cnull_type(), cnull_type()); |
|
} |
|
|
|
template<class A, class B, class C> |
|
typename inherited::template sig<tuple<A&, B&, C&> >::type |
|
operator()(A& a, B& b, C& c) const |
|
{ |
|
return inherited::template call< |
|
typename inherited::template sig<tuple<A&, B&, C&> >::type |
|
>(a, b, c, cnull_type()); |
|
} |
|
|
|
template<class A, class B, class C> |
|
BOOST_LAMBDA_DISABLE_IF_ARRAY3(A, B, C, inherited::template sig<tuple<A const&, B const&, C const&> >) |
|
operator()(A const& a, B const& b, C const& c) const |
|
{ |
|
return inherited::template call< |
|
typename inherited::template sig<tuple<A const&, B const&, C const&> >::type |
|
>(a, b, c, cnull_type()); |
|
} |
|
|
|
// for internal calls with env |
|
template<CALL_TEMPLATE_ARGS> |
|
typename inherited::template sig<tuple<CALL_REFERENCE_TYPES> >::type |
|
internal_call(CALL_FORMAL_ARGS) const { |
|
return inherited::template |
|
call<typename inherited::template |
|
sig<tuple<CALL_REFERENCE_TYPES> >::type>(CALL_ACTUAL_ARGS); |
|
} |
|
|
|
template<class A> |
|
const lambda_functor<lambda_functor_base< |
|
other_action<assignment_action>, |
|
boost::tuple<lambda_functor, |
|
typename const_copy_argument <const A>::type> > > |
|
operator=(const A& a) const { |
|
return lambda_functor_base< |
|
other_action<assignment_action>, |
|
boost::tuple<lambda_functor, |
|
typename const_copy_argument <const A>::type> > |
|
( boost::tuple<lambda_functor, |
|
typename const_copy_argument <const A>::type>(*this, a) ); |
|
} |
|
|
|
template<class A> |
|
const lambda_functor<lambda_functor_base< |
|
other_action<subscript_action>, |
|
boost::tuple<lambda_functor, |
|
typename const_copy_argument <const A>::type> > > |
|
operator[](const A& a) const { |
|
return lambda_functor_base< |
|
other_action<subscript_action>, |
|
boost::tuple<lambda_functor, |
|
typename const_copy_argument <const A>::type> > |
|
( boost::tuple<lambda_functor, |
|
typename const_copy_argument <const A>::type>(*this, a ) ); |
|
} |
|
}; |
|
|
|
#if BOOST_WORKAROUND(BOOST_MSVC, >= 1400) |
|
#pragma warning(pop) |
|
#endif |
|
|
|
} // namespace lambda |
|
} // namespace boost |
|
|
|
// is_placeholder |
|
|
|
#include <boost/is_placeholder.hpp> |
|
|
|
namespace boost |
|
{ |
|
|
|
template<> struct is_placeholder< lambda::lambda_functor< lambda::placeholder<lambda::FIRST> > > |
|
{ |
|
enum _vt { value = 1 }; |
|
}; |
|
|
|
template<> struct is_placeholder< lambda::lambda_functor< lambda::placeholder<lambda::SECOND> > > |
|
{ |
|
enum _vt { value = 2 }; |
|
}; |
|
|
|
template<> struct is_placeholder< lambda::lambda_functor< lambda::placeholder<lambda::THIRD> > > |
|
{ |
|
enum _vt { value = 3 }; |
|
}; |
|
|
|
} // namespace boost |
|
|
|
#endif
|
|
|