/usr/include/boost/functional
Edit: /usr/include/boost/functional/forward_adapter.hpp (16401B)
/*=============================================================================
Copyright (c) 2007-2008 Tobias Schwinger
Use modification and distribution are subject to 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_FUNCTIONAL_FORWARD_ADAPTER_HPP_INCLUDED
# ifndef BOOST_PP_IS_ITERATING
# include
# include
# include
# include
# include
# include
# include
# include
# ifndef BOOST_FUNCTIONAL_FORWARD_ADAPTER_MAX_ARITY
# define BOOST_FUNCTIONAL_FORWARD_ADAPTER_MAX_ARITY 6
# elif BOOST_FUNCTIONAL_FORWARD_ADAPTER_MAX_ARITY < 3
# undef BOOST_FUNCTIONAL_FORWARD_ADAPTER_MAX_ARITY
# define BOOST_FUNCTIONAL_FORWARD_ADAPTER_MAX_ARITY 3
# endif
namespace boost
{
template< typename Function, int Arity_Or_MinArity = -1, int MaxArity = -1 >
class forward_adapter;
//----- ---- --- -- - - - -
namespace detail
{
template< class MostDerived, typename Function, typename FunctionConst,
int Arity, int MinArity >
struct forward_adapter_impl;
struct forward_adapter_result
{
template< typename Sig > struct apply;
// Utility metafunction for qualification adjustment on arguments
template< typename T > struct q { typedef T const t; };
template< typename T > struct q { typedef T const t; };
template< typename T > struct q { typedef T t; };
// Utility metafunction to choose target function qualification
template< typename T > struct c
{ typedef typename T::target_function_t t; };
template< typename T > struct c
{ typedef typename T::target_function_t t; };
template< typename T > struct c
{ typedef typename T::target_function_const_t t; };
template< typename T > struct c
{ typedef typename T::target_function_const_t t; };
};
}
# define BOOST_TMP_MACRO(f,fn,fc) \
boost::detail::forward_adapter_impl< \
forward_adapter, fn, fc, \
(MaxArity!=-1? MaxArity :Arity_Or_MinArity!=-1? Arity_Or_MinArity \
:BOOST_FUNCTIONAL_FORWARD_ADAPTER_MAX_ARITY), \
(Arity_Or_MinArity!=-1? Arity_Or_MinArity : 0) >
template< typename Function, int Arity_Or_MinArity, int MaxArity >
class forward_adapter
: public BOOST_TMP_MACRO(Function,Function,Function const)
, private Function
{
public:
forward_adapter(Function const& f = Function())
: Function(f)
{ }
typedef Function target_function_t;
typedef Function const target_function_const_t;
Function & target_function() { return *this; }
Function const & target_function() const { return *this; }
template< typename Sig > struct result
: detail::forward_adapter_result::template apply
{ };
using BOOST_TMP_MACRO(Function,Function, Function const)::operator();
};
template< typename Function, int Arity_Or_MinArity, int MaxArity >
class forward_adapter< Function const, Arity_Or_MinArity, MaxArity >
: public BOOST_TMP_MACRO(Function const, Function const, Function const)
, private Function
{
public:
forward_adapter(Function const& f = Function())
: Function(f)
{ }
typedef Function const target_function_t;
typedef Function const target_function_const_t;
Function const & target_function() const { return *this; }
template< typename Sig > struct result
: detail::forward_adapter_result::template apply
{ };
using BOOST_TMP_MACRO(Function const,Function const, Function const)
::operator();
};
template< typename Function, int Arity_Or_MinArity, int MaxArity >
class forward_adapter< Function &, Arity_Or_MinArity, MaxArity >
: public BOOST_TMP_MACRO(Function&, Function, Function)
{
Function& ref_function;
public:
forward_adapter(Function& f)
: ref_function(f)
{ }
typedef Function target_function_t;
typedef Function target_function_const_t;
Function & target_function() const { return this->ref_function; }
template< typename Sig > struct result
: detail::forward_adapter_result::template apply
{ };
using BOOST_TMP_MACRO(Function&, Function, Function)::operator();
};
#undef BOOST_TMP_MACRO
namespace detail
{
template< class Self >
struct forward_adapter_result::apply< Self() >
: boost::result_of< BOOST_DEDUCED_TYPENAME c::t() >
{ };
// WHen operator()() doesn't have any parameters, it can't
// be templatized and can't use SFINAE, so intead use class
// template parameter SFINAE to decide whether to instantiate it.
template
struct forward_adapter_sfinae
{
typedef T type;
};
// This is the fallback for when there isn't an operator()(),
// need to create an operator() that will never instantiate
// so that using parent::operator() will work okay.
template< class MD, class F, class FC, class Enable = void>
struct forward_adapter_impl_zero
{
template struct never_instantiate {};
template
typename never_instantiate::type operator()(T) const {}
};
template< class MD, class F, class FC>
struct forward_adapter_impl_zero::type>::type>
{
inline typename boost::result_of< FC() >::type
operator()() const
{
return static_cast(this)->target_function()();
}
inline typename boost::result_of< F() >::type
operator()()
{
return static_cast(this)->target_function()();
}
};
template< class MD, class F, class FC >
struct forward_adapter_impl
: forward_adapter_impl_zero
{
using forward_adapter_impl_zero::operator();
// closing brace gets generated by preprocessing code, below
# define BOOST_TMP_MACRO(tpl_params,arg_types,params,args) \
template< tpl_params > \
inline typename boost::result_of< FC(arg_types) >::type \
operator()(params) const \
{ \
return static_cast(this)->target_function()(args); \
} \
template< tpl_params > \
inline typename boost::result_of< F(arg_types)>::type \
operator()(params) \
{ \
return static_cast(this)->target_function()(args); \
}
# // This is the total number of iterations we need
# define count ((1 << BOOST_FUNCTIONAL_FORWARD_ADAPTER_MAX_ARITY+1)-2)
# // Chain file iteration to virtually one loop
# if BOOST_FUNCTIONAL_FORWARD_ADAPTER_MAX_ARITY <= 7
# define limit1 count
# define limit2 0
# define limit3 0
# else
# if BOOST_FUNCTIONAL_FORWARD_ADAPTER_MAX_ARITY <= 15
# define limit1 (count >> 8)
# define limit2 255
# define limit3 0
# else
# define limit1 (count >> 16)
# define limit2 255
# define limit3 255
# endif
# endif
# define N 0
# define BOOST_PP_FILENAME_1
# define BOOST_PP_ITERATION_LIMITS (0,limit1)
# include BOOST_PP_ITERATE()
# undef N
# undef limit3
# undef limit2
# undef limit1
# undef count
# undef BOOST_TMP_MACRO
};
} // namespace detail
template
struct result_of const ()>
: boost::detail::forward_adapter_result::template apply<
boost::forward_adapter const () >
{ };
template
struct result_of()>
: boost::detail::forward_adapter_result::template apply<
boost::forward_adapter() >
{ };
template
struct result_of const& ()>
: boost::detail::forward_adapter_result::template apply<
boost::forward_adapter const () >
{ };
template
struct result_of& ()>
: boost::detail::forward_adapter_result::template apply<
boost::forward_adapter() >
{ };
}
# define BOOST_FUNCTIONAL_FORWARD_ADAPTER_HPP_INCLUDED
# elif BOOST_PP_ITERATION_DEPTH() == 1 && limit2
# define BOOST_PP_FILENAME_2
# define BOOST_PP_ITERATION_LIMITS (0,limit2)
# include BOOST_PP_ITERATE()
# elif BOOST_PP_ITERATION_DEPTH() == 2 && limit3
# define BOOST_PP_FILENAME_3
# define BOOST_PP_ITERATION_LIMITS (0,limit3)
# include BOOST_PP_ITERATE()
# else
# // I is the loop counter
# if limit2 && limit3
# define I (BOOST_PP_ITERATION_1 << 16 | BOOST_PP_ITERATION_2 << 8 | \
BOOST_PP_ITERATION_3)
# elif limit2
# define I (BOOST_PP_ITERATION_1 << 8 | BOOST_PP_ITERATION_2)
# else
# define I BOOST_PP_ITERATION_1
# endif
# if I < count
# // Done for this arity? Increment N
# if (I+2 >> N+1)
# if N == 0
# undef N
# define N 1
# elif N == 1
# undef N
# define N 2
# elif N == 2
# undef N
# define N 3
# elif N == 3
# undef N
# define N 4
# elif N == 4
# undef N
# define N 5
# elif N == 5
# undef N
# define N 6
# elif N == 6
# undef N
# define N 7
# elif N == 7
# undef N
# define N 8
# elif N == 8
# undef N
# define N 9
# elif N == 9
# undef N
# define N 10
# elif N == 10
# undef N
# define N 11
# elif N == 11
# undef N
# define N 12
# elif N == 12
# undef N
# define N 13
# elif N == 13
# undef N
# define N 14
# elif N == 14
# undef N
# define N 15
# elif N == 15
# undef N
# define N 16
# endif
};
template< class Self, BOOST_PP_ENUM_PARAMS(N,typename T) >
struct forward_adapter_result::apply< Self(BOOST_PP_ENUM_PARAMS(N,T)) >
: boost::result_of<
BOOST_DEDUCED_TYPENAME c::t(BOOST_PP_ENUM_BINARY_PARAMS(N,
typename q::t& BOOST_PP_INTERCEPT)) >
{ };
template< class MD, class F, class FC >
struct forward_adapter_impl
{
template< BOOST_PP_ENUM_PARAMS(N,typename T) >
inline typename boost::result_of< F(
BOOST_PP_ENUM_BINARY_PARAMS(N,T,& BOOST_PP_INTERCEPT)) >::type
operator()(BOOST_PP_ENUM_BINARY_PARAMS(N,T,& BOOST_PP_INTERCEPT));
};
template< class MD, class F, class FC, int MinArity >
struct forward_adapter_impl
: forward_adapter_impl
{
using forward_adapter_impl::operator();
# endif
# // Zero based count for each arity would be I-(1<
inline typename boost::result_of< FC(BOOST_PP_ENUM_PARAMS(N,PT))
>::type
operator()(BOOST_PP_ENUM_BINARY_PARAMS(N,PT,a)) const
{
return static_cast(this)
->target_function()(BOOST_PP_ENUM_PARAMS(N,a));
}
template< BOOST_PP_ENUM_PARAMS(N,typename T) >
inline typename boost::result_of< F(BOOST_PP_ENUM_PARAMS(N,PT))
>::type
operator()(BOOST_PP_ENUM_BINARY_PARAMS(N,PT,a))
{
return static_cast(this)
->target_function()(BOOST_PP_ENUM_PARAMS(N,a));
}
# else
BOOST_TMP_MACRO(BOOST_PP_ENUM_PARAMS(N,typename T),
BOOST_PP_ENUM_PARAMS(N,PT), BOOST_PP_ENUM_BINARY_PARAMS(N,PT,a),
BOOST_PP_ENUM_PARAMS(N,a) )
// ...generates uglier code but is faster - it caches ENUM_*
# endif
# undef PT0
# undef PT1
# undef PT2
# undef PT3
# undef PT4
# undef PT5
# undef PT6
# undef PT7
# undef PT8
# undef PT9
# undef PT10
# undef PT11
# undef PT12
# undef PT13
# undef PT14
# undef PT15
# endif // I < count
# undef I
# endif // defined(BOOST_PP_IS_ITERATING)
#endif // include guard