main page Faq Report bug Feature request Download Doc C++ Modules Namespaces Classes Alphabetical Compound List Files Members Files Members Examples Related Page ximol/assignment.hpp Go to the documentation of this file. /*****************************************************************************\ * * * library XiMoL * * Copyright (C) 2002, 2003, 2004 Florent Tournois * * * * This library is free software; you can redistribute it and/or * * modify it under the terms of the GNU Lesser General Public * * License as published by the Free Software Foundation; either * * version 2.1 of the License, or (at your option) any later version. * * * * This library is distributed in the hope that it will be useful, * * but WITHOUT ANY WARRANTY; without even the implied warranty of * * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * * Lesser General Public License for more details. * * * * You should have received a copy of the GNU Lesser General Public * * License along with this library; if not, write to the Free Software * * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * * * \*****************************************************************************/ //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ /** \file \brief Assignment declaration. In this file, we define all helper for the equality problem. In some cases, we need to assign a const string and then we just want to test the equality. All these helpers are here for this problem. \author Tournois Florent \version 1.0 $Id: assignment.hpp,v 1.11 2004/02/25 18:58:39 tournois Exp $ $Log: assignment.hpp,v $ Revision 1.11 2004/02/25 18:58:39 tournois imporve the gcc compatibility. Revision 1.10 2004/02/25 15:57:06 tournois no message Revision 1.9 2004/02/22 22:36:23 hfp *** empty log message *** Revision 1.8 2004/02/22 10:27:32 tournois Add some doc. Revision 1.7 2004/02/22 09:54:19 tournois Change years on the copyright. Revision 1.6 2004/02/15 10:04:36 hfp * assignment_private_helper: all the things are already part of boost... * select -> mpl::if_c * equal -> now use of equal is more specified to boost::type_traits: is_const, is_convertible, ... * assignment (struct) is more special: test_equality is also selected in case of arrays Revision 1.5 2004/01/29 20:52:35 tournois doc and tutorial. Revision 1.4 2004/01/27 21:49:51 tournois Add docs and tutorial. Revision 1.3 2004/01/19 20:40:55 tournois Add min, max and digits facet. Create the control flow file. Revision 1.2 2004/01/18 11:40:58 tournois Add the pattern facet. Revision 1.1 2004/01/08 20:02:29 tournois Add XIMOL_XML_NAMESPACE_PATH::comment and assignment mainuplator. */ //++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ #ifndef XIMOL_ASSIGNMENT_HPP_ #define XIMOL_ASSIGNMENT_HPP_ #include <ximol/str_cast.hpp> #include <ximol/error.hpp> #include <ximol/translation.hpp> #include <boost/mpl/if.hpp> #include <boost/type_traits.hpp> XIMOL_BEGIN_NAMESPACE //----------------------------------------------------------------------------- /** A small namespace to hide the dirty stuff. * In this namespace we have define some classic type manipulation. */ //----------------------------------------------------------------------------- namespace assignment_private_helper { /// test the character type for the serialisation template<typename T> struct char_type_choice { typedef typename ::boost::mpl::if_c< ::boost::is_convertible<T, ::std::string const&>::value, // condition ::std::string, // if true ::std::wstring // else case >::type type; }; }; // end of the namespace assignment_private_helper //----------------------------------------------------------------------------- /** Namespace for the assignment test option. * If we need to test the equality, here are some possibility. */ //----------------------------------------------------------------------------- namespace assignment_test_equality_policy { /// throw error when test are false struct error_policy_throw { static void object_are_different(){ XIMOL_THROW << _(L"The two value should be equal") << XIMOL_AS_ERROR; }; }; /// standard equality (x==y) template < typename policy = error_policy_throw > struct standard { template<typename T, typename U> static void value(T const& t_, U const& u_) { if (! (u_==t_) ) policy::object_are_different(); }; }; /// test with small char serialisation template < typename policy = error_policy_throw > struct char_serialization { template<typename T, typename U> static void value(T const& t_, U const& u_) { if(str< ::std::string>::cast(u_)!=str< ::std::string>::cast(t_)) policy::object_are_different(); } }; /// test with wide char serialisation template < typename policy = error_policy_throw > struct wchar_serialization { template<typename T, typename U> static void value(T const& t_, U const& u_) { if(str< ::std::wstring>::cast(u_)!=str< ::std::wstring>::cast(t_)) policy::object_are_different(); } }; /// test with char (choose at compile time serialisation) template < typename policy = error_policy_throw > struct serialization { template<typename T, typename U> static void value(T const& t_, U const& u_) { using namespace assignment_private_helper; if(str< typename char_type_choice<T>::type >::cast(u_)!=str< typename char_type_choice<T>::type >::cast(t_)) policy::object_are_different(); } }; }; // end of namespace assignment_test_equality_policy //----------------------------------------------------------------------------- /** Namespace for the assignment option. * If we need to assign something, here are some possibility. */ //----------------------------------------------------------------------------- namespace assignment_equality_policy { /// standard assignment (x=y) struct standard { template<typename T, typename U> static void value(T& t_, U const& u_) { t_ = u_ ; } }; /// assignment with small char serialization struct char_serialization { template<typename T, typename U> static void value(T& t_, U const& u_) { ::std::istringstream is(str<std::string>::cast(u_)); is >> t_; } }; /// assignment with wide char serialization struct wchar_serialization { template<typename T, typename U> static void value(T& t_, U const& u_) { ::std::wistringstream is(str<std::wstring>::cast(u_)); is >> t_; } }; /// assignment to a string struct to_string { template<typename T, typename U> static void value(T& t_, U const& u_) { using namespace assignment_private_helper; t_ = str< typename char_type_choice<T>::type >::cast(u_).c_str(); } }; }; // end of namespace assignment_equality_policy //============================================================================= /** Assignment struct with options. * assign type is the assignment option * test_equality is the test type option */ //============================================================================= template<typename assign, typename test_equality> struct assignment { template<typename T, typename U> static T& equality(T& t_, U const& u_) { ::boost::mpl::if_c< ::boost::is_const<T>::value || // condition A ::boost::is_array<T>::value, // condition B: an assign could be specialized for arrays, but... test_equality, // true assign // false >::type::value(t_, u_); return t_; } }; ///@name assignment type defined //@{ /// assignment for string type typedef assignment<assignment_equality_policy::to_string, assignment_test_equality_policy::serialization<> > assignment_to_string; /// assignment standard typedef assignment<assignment_equality_policy::standard, assignment_test_equality_policy::standard<> > assignment_std; /// assignment with small char serialization typedef assignment<assignment_equality_policy::char_serialization, assignment_test_equality_policy::char_serialization<> > assignment_char_serialization; /// assignment with wide char serialization typedef assignment<assignment_equality_policy::char_serialization, assignment_test_equality_policy::char_serialization<> > assignment_wchar_serialization; //@} XIMOL_END_NAMESPACE #endif // #ifndef XIMOL_ASSIGNMENT_HPP_

---

If you have any questions about XiMoL, you could write to tournois@users.sourceforge.net.

---