epoc32/include/stdapis/boost/utility/value_init.hpp
author William Roberts <williamr@symbian.org>
Tue, 16 Mar 2010 16:12:26 +0000
branchSymbian2
changeset 2 2fe1408b6811
permissions -rw-r--r--
Final list of Symbian^2 public API header files
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// Copyright 2002, Fernando Luis Cacciola Carballal.
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//
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// Distributed under the Boost Software License, Version 1.0. (See
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// accompanying file LICENSE_1_0.txt or copy at
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// http://www.boost.org/LICENSE_1_0.txt)
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//
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// 21 Ago 2002 (Created) Fernando Cacciola
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//
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#ifndef BOOST_UTILITY_VALUE_INIT_21AGO2002_HPP
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#define BOOST_UTILITY_VALUE_INIT_21AGO2002_HPP
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#include "boost/detail/select_type.hpp"
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#include "boost/type_traits/cv_traits.hpp"
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namespace boost {
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namespace vinit_detail {
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template<class T>
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class const_T_base
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{
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  protected :
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   const_T_base() : x() {}
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   T x ;
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} ;
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template<class T>
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struct non_const_T_base
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{
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  protected :
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   non_const_T_base() : x() {}
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   mutable T x ;
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} ;
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template<class T>
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struct select_base
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{
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  typedef typename
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    boost::detail::if_true< ::boost::is_const<T>::value >
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      ::template then< const_T_base<T>, non_const_T_base<T> >::type type ;
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} ;
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} // namespace vinit_detail
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template<class T>
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class value_initialized : private vinit_detail::select_base<T>::type
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{
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  public :
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    value_initialized() {}
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    operator T&() const { return this->x ; }
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    T& data() const { return this->x ; }
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} ;
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template<class T>
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T const& get ( value_initialized<T> const& x )
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{
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  return x.data() ;
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}
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template<class T>
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T& get ( value_initialized<T>& x )
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{
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  return x.data() ;
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}
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} // namespace boost
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#endif
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