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