csutil/typetraits.h Source File (Crystal Space 2.0 Public API Reference)

| ## Public API Reference

- Main Page
- Related Pages
- Modules
- Namespaces
- Classes
- Files

- File List
- File Members

csutil/typetraits.h
Go to the documentation of this file.

    00001 /*
    00002   Copyright (C) 2006 by Marten Svanfeldt
    00003
    00004   This library is free software; you can redistribute it and/or
    00005   modify it under the terms of the GNU Library General Public
    00006   License as published by the Free Software Foundation; either
    00007   version 2 of the License, or (at your option) any later version.
    00008
    00009   This library is distributed in the hope that it will be useful,
    00010   but WITHOUT ANY WARRANTY; without even the implied warranty of
    00011   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    00012   Library General Public License for more details.
    00013
    00014   You should have received a copy of the GNU Library General Public
    00015   License along with this library; if not, write to the Free
    00016   Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
    00017 */
    00018
    00019 #ifndef __CSUTIL_TYPETRAITS_H__
    00020 #define __CSUTIL_TYPETRAITS_H__
    00021
    00027 namespace CS
    00028 {
    00029   namespace Meta
    00030   {
    00031     namespace Implementation
    00032     {
    00033       // Types for checking yes/no
    00034
    00036       typedef char YesType;
    00037
    00039       struct NoType
    00040       {
    00041         char padding[8];
    00042       };
    00043
    00045       template <class T>
    00046       struct Wrap { Wrap () {} };
    00047
    00048       template <class T> T&(* IsReferenceHelper1(Wrap<T>) )(Wrap<T>);
    00049       char IsReferenceHelper1(...);
    00050
    00051       template <class T> NoType IsReferenceHelper2(T&(*)(Wrap<T>));
    00052       YesType IsReferenceHelper2(...);
    00053
    00054       template <class T>
    00055       struct IsReferenceImpl
    00056       {
    00057         static const bool value = sizeof(IsReferenceHelper2 (
    00058           IsReferenceHelper1 (Wrap<T>()))) == 1;
    00059       };
    00060
    00061
    00062       template <bool b1, bool b2, bool b3 = true, bool b4 = true, bool b5 = true,
    00063                 bool b6 = true, bool b7 = true>
    00064       struct TraitAnd;
    00065
    00066       template <bool b1, bool b2, bool b3, bool b4, bool b5, bool b6, bool b7>
    00067       struct TraitAnd
    00068       {
    00069         static const bool value = false;
    00070       };
    00071
    00072       template <>
    00073       struct TraitAnd<true, true, true, true, true, true, true>
    00074       {
    00075         static const bool value = true;
    00076       };
    00077
    00078       template <bool b1, bool b2, bool b3 = false, bool b4 = false, bool b5 = false,
    00079                 bool b6 = false, bool b7 = false>
    00080       struct TraitOr;
    00081
    00082       template <bool b1, bool b2, bool b3, bool b4, bool b5, bool b6, bool b7>
    00083       struct TraitOr
    00084       {
    00085         static const bool value = true;
    00086       };
    00087
    00088       template<>
    00089       struct TraitOr<false, false, false, false, false, false, false>
    00090       {
    00091         static const bool value = false;
    00092       };
    00093
    00094       template <class T>
    00095       YesType IsSameTester(T*, T*);
    00096
    00097       NoType IsSameTester(...);
    00098
    00099       template <class T, class U>
    00100       struct IsSameImpl
    00101       {
    00102         static T* t;
    00103         static U* u;
    00104
    00105         static const bool value = TraitAnd<
    00106           sizeof(YesType) == sizeof(IsSameTester(t, u)),
    00107           IsReferenceImpl<T>::value == IsReferenceImpl<U>::value,
    00108           sizeof(T) == sizeof(U)>::value;
    00109       };
    00110
    00111       template<typename B, typename D>
    00112       struct IsBaseOfHelper
    00113       {
    00114         operator const B*() const;
    00115         operator const D*();
    00116       };
    00117
    00118       template<typename B, typename D>
    00119       struct IsBaseOfImpl
    00120       {
    00121         template<typename T>
    00122         static YesType Test(const D*,T);
    00123         static NoType Test(const B*,int);
    00124         static const bool value = TraitOr<
    00125           sizeof(YesType) == sizeof(Test(IsBaseOfHelper<B,D>(),0)),
    00126           IsSameImpl<B,D>::value>::value;
    00127       };
    00128     } // namespace Implementation
    00129
    00130
    00134     template <class Type>
    00135     struct IsReference
    00136     {
    00137       static const bool value = CS::Meta::Implementation
    00138         ::IsReferenceImpl<Type>::value;
    00139     };
    00140
    00144     template <class Type1, class Type2>
    00145     struct IsSame
    00146     {
    00147       static const bool value = CS::Meta::Implementation
    00148         ::IsSameImpl<Type1, Type2>::value;
    00149     };
    00150
    00154     template <class Type1, class Type2>
    00155     struct IsBaseOf
    00156     {
    00157       static const bool value = CS::Meta::Implementation
    00158         ::IsBaseOfImpl<Type1, Type2>::value;
    00159     };
    00160   } // namespace TypeTraits
    00161
    00162 } // namespace CS
    00163
    00164 #endif