325 lines
9.9 KiB
C++
325 lines
9.9 KiB
C++
// 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
|