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			Plaintext
		
	
	
	
	
	
		
		
			
		
	
	
			107 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
|   | //----------------------------------------------------------------------------- | ||
|  | // boost blank.hpp header file | ||
|  | // See http://www.boost.org for updates, documentation, and revision history. | ||
|  | //----------------------------------------------------------------------------- | ||
|  | // | ||
|  | // Copyright (c) 2003 | ||
|  | // Eric Friedman | ||
|  | // | ||
|  | // 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) | ||
|  | 
 | ||
|  | #ifndef BOOST_BLANK_HPP | ||
|  | #define BOOST_BLANK_HPP | ||
|  | 
 | ||
|  | #include "boost/blank_fwd.hpp" | ||
|  | 
 | ||
|  | #if !defined(BOOST_NO_IOSTREAM) | ||
|  | #include <iosfwd> // for std::basic_ostream forward declare | ||
|  | #include "boost/detail/templated_streams.hpp" | ||
|  | #endif // BOOST_NO_IOSTREAM | ||
|  | 
 | ||
|  | #include "boost/mpl/bool.hpp" | ||
|  | #include "boost/type_traits/is_empty.hpp" | ||
|  | #include "boost/type_traits/is_pod.hpp" | ||
|  | #include "boost/type_traits/is_stateless.hpp" | ||
|  | 
 | ||
|  | namespace boost { | ||
|  | 
 | ||
|  | struct blank | ||
|  | { | ||
|  | }; | ||
|  | 
 | ||
|  | // type traits specializations | ||
|  | // | ||
|  | 
 | ||
|  | template <> | ||
|  | struct is_pod< blank > | ||
|  |     : mpl::true_ | ||
|  | { | ||
|  | }; | ||
|  | 
 | ||
|  | template <> | ||
|  | struct is_empty< blank > | ||
|  |     : mpl::true_ | ||
|  | { | ||
|  | }; | ||
|  | 
 | ||
|  | template <> | ||
|  | struct is_stateless< blank > | ||
|  |     : mpl::true_ | ||
|  | { | ||
|  | }; | ||
|  | 
 | ||
|  | // relational operators | ||
|  | // | ||
|  | 
 | ||
|  | inline bool operator==(const blank&, const blank&) | ||
|  | { | ||
|  |     return true; | ||
|  | } | ||
|  | 
 | ||
|  | inline bool operator<=(const blank&, const blank&) | ||
|  | { | ||
|  |     return true; | ||
|  | } | ||
|  | 
 | ||
|  | inline bool operator>=(const blank&, const blank&) | ||
|  | { | ||
|  |     return true; | ||
|  | } | ||
|  | 
 | ||
|  | inline bool operator!=(const blank&, const blank&) | ||
|  | { | ||
|  |     return false; | ||
|  | } | ||
|  | 
 | ||
|  | inline bool operator<(const blank&, const blank&) | ||
|  | { | ||
|  |     return false; | ||
|  | } | ||
|  | 
 | ||
|  | inline bool operator>(const blank&, const blank&) | ||
|  | { | ||
|  |     return false; | ||
|  | } | ||
|  | 
 | ||
|  | // streaming support | ||
|  | // | ||
|  | #if !defined(BOOST_NO_IOSTREAM) | ||
|  | 
 | ||
|  | BOOST_TEMPLATED_STREAM_TEMPLATE(E,T) | ||
|  | inline BOOST_TEMPLATED_STREAM(ostream, E,T)& operator<<( | ||
|  |       BOOST_TEMPLATED_STREAM(ostream, E,T)& out | ||
|  |     , const blank& | ||
|  |     ) | ||
|  | { | ||
|  |     // (output nothing) | ||
|  |     return out; | ||
|  | } | ||
|  | 
 | ||
|  | #endif // BOOST_NO_IOSTREAM | ||
|  | 
 | ||
|  | } // namespace boost | ||
|  | 
 | ||
|  | #endif // BOOST_BLANK_HPP |