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- /*-----------------------------------------------------------------------------+
- Copyright (c) 2008-2010: Joachim Faulhaber
- +------------------------------------------------------------------------------+
- Distributed under the Boost Software License, Version 1.0.
- (See accompanying file LICENCE.txt or copy at
- http://www.boost.org/LICENSE_1_0.txt)
- +-----------------------------------------------------------------------------*/
- #ifndef BOOST_ICL_TYPE_TRAITS_UNIT_ELEMENT_HPP_JOFA_080912
- #define BOOST_ICL_TYPE_TRAITS_UNIT_ELEMENT_HPP_JOFA_080912
- #include <string>
- #include <boost/icl/type_traits/identity_element.hpp>
- #include <boost/icl/type_traits/succ_pred.hpp>
- namespace boost{ namespace icl
- {
- template <class Type> struct unit_element{ static Type value(); };
- template<> inline bool unit_element<bool>::value() { return true;}
- template<> inline float unit_element<float>::value() { return 1.0; }
- template<> inline double unit_element<double>::value() { return 1.0; }
- template<> inline long double unit_element<long double>::value()
- { return 1.0; }
-
- // Smallest 'visible' string that is greater than the empty string.
- template <>
- inline std::string unit_element<std::string>::value()
- { return std::string(" "); }
- template <class Type>
- inline Type unit_element<Type>::value()
- { return icl::succ(identity_element<Type>::value()); }
- }} // namespace boost icl
- #endif
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