type-traits.h

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/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
/*
 * Copyright (c) 2007 INRIA
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation;
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#ifndef TYPE_TRAITS_H
#define TYPE_TRAITS_H

#include "ptr.h"

namespace ns3 {
  
template <typename T>
struct TypeTraits
{
private:
  struct NullType {};
  template <typename U> struct UnConst
  {
    typedef U Result;                             
  };
  template <typename U> struct UnConst<const U>
  {
    typedef U Result;                             
  };
  template <typename U> struct ReferenceTraits
  {  enum { IsReference = 0          };
    typedef U ReferencedType;                     
  };
  template <typename U> struct ReferenceTraits<U&>
  {  enum { IsReference = 1          };
    typedef U ReferencedType;                     
  };
  template <typename U> struct PointerTraits
  {  enum { IsPointer = 0,          
                          IsPtr = 0               };
    typedef U PointeeType;                        
  };
  template <typename U> struct PointerTraits<U *>
  {  enum { IsPointer = 1,          
                          IsPtr = 0               };
    typedef U PointeeType;                        
  };  
  template <typename U> struct PointerTraits<ns3::Ptr<U> >
  {  enum { IsPointer = 0,          
                          IsPtr = 1               };
    typedef U PointeeType;                        
  };
  template <typename U> struct Base
  {
    typedef U Type;                               
  };
  template <typename U> struct Base <U &>
  {
    typedef typename Base<U>::Type Type;          
  };
  template <typename U> struct Base <U *>
  {
    typedef typename Base<U>::Type  Type;         
  };
  template <typename U> struct Base <const U >
  {
    typedef typename Base<U>::Type  Type;         
  };
  template <typename U> struct PtrBase
  {
    typedef U Type;                               
  };
  template <typename U> struct PtrBase <ns3::Ptr<U> >
  {
    typedef U Type;                               
  };
  template <typename U> struct FunctionPtrTraits
  {  enum { IsFunctionPointer = 0    };
    typedef NullType ReturnType;                  
  };
  template <typename U>
  struct FunctionPtrTraits <U (*)(void)>
  {  enum { IsFunctionPointer = 1    };  enum { nArgs = 0                };
    typedef U ReturnType;                         
  };
  template <typename U,
            typename V1>
  struct FunctionPtrTraits <U (*)(V1)>
  {  enum { IsFunctionPointer = 1    };  enum { nArgs = 1                };
    typedef U ReturnType;                         
    typedef V1 Arg1Type;                          
  };
  template <typename U,
            typename V1, typename V2>
  struct FunctionPtrTraits <U (*)(V1,V2)>
  {  enum { IsFunctionPointer = 1    };  enum { nArgs = 2                };
    typedef U ReturnType;                         
    typedef V1 Arg1Type;                          
    typedef V2 Arg2Type;                          
  };
  template <typename U,
            typename V1, typename V2, typename V3>
  struct FunctionPtrTraits <U (*)(V1,V2,V3)>
  {  enum { IsFunctionPointer = 1    };  enum { nArgs = 3                };
    typedef U ReturnType;                         
    typedef V1 Arg1Type;                          
    typedef V2 Arg2Type;                          
    typedef V3 Arg3Type;                          
  };
  template <typename U,
            typename V1, typename V2, typename V3,
            typename V4>
  struct FunctionPtrTraits <U (*)(V1,V2,V3,V4)>
  {  enum { IsFunctionPointer = 1    };  enum { nArgs = 4                };
    typedef U ReturnType;                         
    typedef V1 Arg1Type;                          
    typedef V2 Arg2Type;                          
    typedef V3 Arg3Type;                          
    typedef V4 Arg4Type;                          
  };
  template <typename U,
            typename V1, typename V2, typename V3,
            typename V4, typename V5>
  struct FunctionPtrTraits <U (*)(V1,V2,V3,V4,V5)>
  {  enum { IsFunctionPointer = 1    };  enum { nArgs = 5                };
    typedef U ReturnType;                         
    typedef V1 Arg1Type;                          
    typedef V2 Arg2Type;                          
    typedef V3 Arg3Type;                          
    typedef V4 Arg4Type;                          
    typedef V5 Arg5Type;                          
  };
  template <typename U,
            typename V1, typename V2, typename V3,
            typename V4, typename V5, typename V6>
  struct FunctionPtrTraits <U (*)(V1,V2,V3,V4,V5,V6)>
  {  enum { IsFunctionPointer = 1    };  enum { nArgs = 6                };
    typedef U ReturnType;                         
    typedef V1 Arg1Type;                          
    typedef V2 Arg2Type;                          
    typedef V3 Arg3Type;                          
    typedef V4 Arg4Type;                          
    typedef V5 Arg5Type;                          
    typedef V6 Arg6Type;                          
  };
  template <typename U> struct PtrToMemberTraits
  {  enum { IsPointerToMember = 0    };
  };
  template <typename U,  typename V>
  struct PtrToMemberTraits <U (V::*) (void)>
  {  enum { IsPointerToMember = 1    };  enum { nArgs = 0                };
    typedef U ReturnType;                         
  };
  template <typename U,  typename V>
  struct PtrToMemberTraits <U (V::*) (void) const>
  {  enum { IsPointerToMember = 1    };  enum { nArgs = 0                };
    typedef U ReturnType;                         
  };
  template <typename U,  typename V,
            typename W1>
  struct PtrToMemberTraits <U (V::*) (W1)>
  {  enum { IsPointerToMember = 1    };  enum { nArgs = 1                };
    typedef U ReturnType;                         
    typedef W1 Arg1Type;                          
  };
  template <typename U,  typename V,
            typename W1>
  struct PtrToMemberTraits <U (V::*) (W1) const>
  {  enum { IsPointerToMember = 1    };  enum { nArgs = 1                };
    typedef U ReturnType;                         
    typedef W1 Arg1Type;                          
  };
  template <typename U,  typename V,
            typename W1, typename W2>
  struct PtrToMemberTraits <U (V::*) (W1,W2)>
  {  enum { IsPointerToMember = 1    };  enum { nArgs = 2                };
    typedef U ReturnType;                         
    typedef W1 Arg1Type;                          
    typedef W2 Arg2Type;                          
  };
  template <typename U,  typename V,
            typename W1, typename W2>
  struct PtrToMemberTraits <U (V::*) (W1,W2) const>
  {  enum { IsPointerToMember = 1    };  enum { nArgs = 2                };
    typedef U ReturnType;                         
    typedef W1 Arg1Type;                          
    typedef W2 Arg2Type;                          
  };
  template <typename U,  typename V,
            typename W1, typename W2, typename W3>
  struct PtrToMemberTraits <U (V::*) (W1,W2,W3)>
  {  enum { IsPointerToMember = 1    };  enum { nArgs = 3                };
    typedef U ReturnType;                         
    typedef W1 Arg1Type;                          
    typedef W2 Arg2Type;                          
    typedef W3 Arg3Type;                          
  };
  template <typename U,  typename V,
            typename W1, typename W2, typename W3>
  struct PtrToMemberTraits <U (V::*) (W1,W2,W3) const>
  {  enum { IsPointerToMember = 1    };  enum { nArgs = 3                };
    typedef U ReturnType;                         
    typedef W1 Arg1Type;                          
    typedef W2 Arg2Type;                          
    typedef W3 Arg3Type;                          
  };
  template <typename U,  typename V,
            typename W1, typename W2, typename W3,
            typename W4>
  struct PtrToMemberTraits <U (V::*) (W1,W2,W3,W4)>
  {  enum { IsPointerToMember = 1    };  enum { nArgs = 4                };
    typedef U ReturnType;                         
    typedef W1 Arg1Type;                          
    typedef W2 Arg2Type;                          
    typedef W3 Arg3Type;                          
    typedef W4 Arg4Type;                          
  };
  template <typename U,  typename V,
            typename W1, typename W2, typename W3,
            typename W4>
  struct PtrToMemberTraits <U (V::*) (W1,W2,W3,W4) const>
  {  enum { IsPointerToMember = 1    };  enum { nArgs = 4                };
    typedef U ReturnType;                         
    typedef W1 Arg1Type;                          
    typedef W2 Arg2Type;                          
    typedef W3 Arg3Type;                          
    typedef W4 Arg4Type;                          
  };
  template <typename U,  typename V,
            typename W1, typename W2, typename W3,
            typename W4, typename W5>
  struct PtrToMemberTraits <U (V::*) (W1,W2,W3,W4,W5)>
  {  enum { IsPointerToMember = 1    };  enum { nArgs = 5                };
    typedef U ReturnType;                         
    typedef W1 Arg1Type;                          
    typedef W2 Arg2Type;                          
    typedef W3 Arg3Type;                          
    typedef W4 Arg4Type;                          
    typedef W5 Arg5Type;                          
  };
  template <typename U,  typename V,
            typename W1, typename W2, typename W3,
            typename W4, typename W5>
  struct PtrToMemberTraits <U (V::*) (W1,W2,W3,W4,W5) const>
  {  enum { IsPointerToMember = 1    };  enum { nArgs = 5                };
    typedef U ReturnType;                         
    typedef W1 Arg1Type;                          
    typedef W2 Arg2Type;                          
    typedef W3 Arg3Type;                          
    typedef W4 Arg4Type;                          
    typedef W5 Arg5Type;                          
  };
  template <typename U,  typename V,
            typename W1, typename W2, typename W3,
            typename W4, typename W5, typename W6>
  struct PtrToMemberTraits <U (V::*) (W1,W2,W3,W4,W5,W6)>
  {  enum { IsPointerToMember = 1    };  enum { nArgs = 6                };
    typedef U ReturnType;                         
    typedef W1 Arg1Type;                          
    typedef W2 Arg2Type;                          
    typedef W3 Arg3Type;                          
    typedef W4 Arg4Type;                          
    typedef W5 Arg5Type;                          
    typedef W6 Arg6Type;                          
  };
  template <typename U,  typename V,
            typename W1, typename W2, typename W3,
            typename W4, typename W5, typename W6>
  struct PtrToMemberTraits <U (V::*) (W1,W2,W3,W4,W5,W6) const>
  {  enum { IsPointerToMember = 1    };  enum { nArgs = 6                };
    typedef U ReturnType;                         
    typedef W1 Arg1Type;                          
    typedef W2 Arg2Type;                          
    typedef W3 Arg3Type;                          
    typedef W4 Arg4Type;                          
    typedef W5 Arg5Type;                          
    typedef W6 Arg6Type;                          
  };

public:
  typedef typename UnConst<T>::Result NonConstType;
  typedef typename ReferenceTraits<T>::ReferencedType ReferencedType;
  typedef typename PointerTraits<T>::PointeeType PointeeType;
  typedef typename Base<T>::Type BaseType;
  typedef typename PtrBase<T>::Type PtrBaseType;
  enum {
    IsPointerToMember = PtrToMemberTraits<T>::IsPointerToMember,
    IsPointer = PointerTraits<T>::IsPointer,
    IsPtr = PointerTraits<T>::IsPtr,
    IsReference = ReferenceTraits<T>::IsReference,
    IsFunctionPointer = FunctionPtrTraits<T>::IsFunctionPointer
  };
  typedef PtrToMemberTraits<T> PointerToMemberTraits;
  typedef FunctionPtrTraits<T> FunctionPointerTraits;
};

}  // namespace ns3

#endif /* TYPE_TRAITS_H */