111 lines
		
	
	
		
			2.9 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
		
		
			
		
	
	
			111 lines
		
	
	
		
			2.9 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
|   | // -- Boost Lambda Library ------------------------------------------------- | ||
|  | 
 | ||
|  | // 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 www.boost.org | ||
|  | 
 | ||
|  | // -------------------------------------------------- | ||
|  | 
 | ||
|  | #ifndef BOOST_LAMBDA_ARITY_CODE_HPP | ||
|  | #define BOOST_LAMBDA_ARITY_CODE_HPP | ||
|  | 
 | ||
|  | #include "boost/type_traits/cv_traits.hpp" | ||
|  | #include "boost/type_traits/transform_traits.hpp" | ||
|  | 
 | ||
|  | namespace boost {  | ||
|  | namespace lambda { | ||
|  | 
 | ||
|  | // These constants state, whether a lambda_functor instantiation results from  | ||
|  | // an expression which contains no placeholders (NONE),  | ||
|  | // only free1 placeholders (FIRST),  | ||
|  | // free2 placeholders and maybe free1 placeholders (SECOND), | ||
|  | // free3 and maybe free1 and free2 placeholders (THIRD), | ||
|  | // freeE placeholders and maybe free1 and free2  (EXCEPTION). | ||
|  | // RETHROW means, that a rethrow expression is used somewhere in the lambda_functor. | ||
|  | 
 | ||
|  | enum { NONE             = 0x00, // Notice we are using bits as flags here. | ||
|  |        FIRST            = 0x01,  | ||
|  |        SECOND           = 0x02,  | ||
|  |        THIRD            = 0x04,  | ||
|  |        EXCEPTION        = 0x08,  | ||
|  |        RETHROW          = 0x10}; | ||
|  | 
 | ||
|  | 
 | ||
|  | template<class T> | ||
|  | struct get_tuple_arity; | ||
|  | 
 | ||
|  | namespace detail { | ||
|  | 
 | ||
|  | template <class T> struct get_arity_; | ||
|  | 
 | ||
|  | } // end detail; | ||
|  | 
 | ||
|  | template <class T> struct get_arity { | ||
|  | 
 | ||
|  |   BOOST_STATIC_CONSTANT(int, value = detail::get_arity_<typename boost::remove_cv<typename boost::remove_reference<T>::type>::type>::value); | ||
|  | 
 | ||
|  | }; | ||
|  | 
 | ||
|  | namespace detail { | ||
|  | 
 | ||
|  | template<class T> | ||
|  | struct get_arity_ { | ||
|  |   BOOST_STATIC_CONSTANT(int, value = 0); | ||
|  | }; | ||
|  | 
 | ||
|  | template<class T> | ||
|  | struct get_arity_<lambda_functor<T> > { | ||
|  |   BOOST_STATIC_CONSTANT(int, value = get_arity<T>::value); | ||
|  | }; | ||
|  | 
 | ||
|  | template<class Action, class Args> | ||
|  | struct get_arity_<lambda_functor_base<Action, Args> > { | ||
|  |   BOOST_STATIC_CONSTANT(int, value = get_tuple_arity<Args>::value); | ||
|  | }; | ||
|  | 
 | ||
|  | template<int I> | ||
|  | struct get_arity_<placeholder<I> > { | ||
|  |   BOOST_STATIC_CONSTANT(int, value = I); | ||
|  | }; | ||
|  | 
 | ||
|  | } // detail  | ||
|  | 
 | ||
|  | template<class T> | ||
|  | struct get_tuple_arity { | ||
|  |   BOOST_STATIC_CONSTANT(int, value = get_arity<typename T::head_type>::value | get_tuple_arity<typename T::tail_type>::value); | ||
|  | }; | ||
|  | 
 | ||
|  | 
 | ||
|  | template<> | ||
|  | struct get_tuple_arity<null_type> { | ||
|  |   BOOST_STATIC_CONSTANT(int, value = 0); | ||
|  | }; | ||
|  | 
 | ||
|  | 
 | ||
|  |   // Does T have placeholder<I> as it's subexpression? | ||
|  | 
 | ||
|  | template<class T, int I> | ||
|  | struct has_placeholder { | ||
|  |   BOOST_STATIC_CONSTANT(bool, value = (get_arity<T>::value & I) != 0); | ||
|  | };  | ||
|  | 
 | ||
|  | template<int I, int J> | ||
|  | struct includes_placeholder { | ||
|  |   BOOST_STATIC_CONSTANT(bool, value = (J & I) != 0); | ||
|  | }; | ||
|  | 
 | ||
|  | template<int I, int J> | ||
|  | struct lacks_placeholder { | ||
|  |   BOOST_STATIC_CONSTANT(bool, value = ((J & I) == 0)); | ||
|  | }; | ||
|  | 
 | ||
|  | 
 | ||
|  | } // namespace lambda | ||
|  | } // namespace boost | ||
|  | 
 | ||
|  | #endif |