ahFunction.H

// Functor implementations -*- C++ -*-

/*
 *
 * Copyright (c) 1994
 * Hewlett-Packard Company
 *
 * Permission to use, copy, modify, distribute and sell this software
 * and its documentation for any purpose is hereby granted without fee,
 * provided that the above copyright notice appear in all copies and
 * that both that copyright notice and this permission notice appear
 * in supporting documentation.  Hewlett-Packard Company makes no
 * representations about the suitability of this software for any
 * purpose.  It is provided "as is" without express or implied warranty.
 *
 *
 * Copyright (c) 1996-1998
 * Silicon Graphics Computer Systems, Inc.
 *
 * Permission to use, copy, modify, distribute and sell this software
 * and its documentation for any purpose is hereby granted without fee,
 * provided that the above copyright notice appear in all copies and
 * that both that copyright notice and this permission notice appear
 * in supporting documentation.  Silicon Graphics makes no
 * representations about the suitability of this software for any
 * purpose.  It is provided "as is" without express or implied warranty.
 */

# ifndef AHFUNCTION_H
# define AHFUNCTION_H 

# include <utility>

namespace Aleph
{

      template <class _Arg, class _Result>
  struct unary_function
  {
    typedef _Arg argument_type;  
    typedef _Result result_type; 
  };

      template <class _Arg1, class _Arg2, class _Result>
  struct binary_function
  {
    typedef _Arg1 first_argument_type;   // the type of the first argument
    typedef _Arg2 second_argument_type;  // the type of the second argument
    typedef _Result result_type;         // type of the return type
  };


      template <class _Tp>
  struct plus : public binary_function<_Tp, _Tp, _Tp>
  {
    _Tp operator () (const _Tp& __x, const _Tp& __y) const
    {
      return __x + __y; 
    }
  };


      template <class _Tp>
  struct minus : public binary_function<_Tp, _Tp, _Tp>
  {
    _Tp 
    operator () (const _Tp& __x, const _Tp& __y) const
    { 
      return __x - __y; 
    }
  };


      template <class _Tp>
  struct multiplies : public binary_function<_Tp, _Tp, _Tp>
  {
    _Tp operator () (const _Tp& __x, const _Tp& __y) const
    {
      return __x * __y; 
    }
  };


      template <class _Tp>
  struct divides : public binary_function<_Tp, _Tp, _Tp>
  {
    _Tp operator () (const _Tp& __x, const _Tp& __y) const
    { 
      return __x / __y; 
    }
  };


      template <class _Tp>
  struct modulus : public binary_function<_Tp, _Tp, _Tp>
  {
    _Tp operator () (const _Tp& __x, const _Tp& __y) const
    { 
      return __x % __y; 
    }
  };


      template <class _Tp>
  struct negate : public unary_function<_Tp, _Tp>
  {
    _Tp operator () (const _Tp& __x) const
    { 
      return -__x; 
    }
  };


      template <class _Tp>
  struct equal_to : public binary_function<_Tp, _Tp, bool>
  {
    bool operator () (const _Tp& __x, const _Tp& __y) const
    { 
      return __x == __y; 
    }
  };


      template <class _Tp>
  struct not_equal_to : public binary_function<_Tp, _Tp, bool>
  {
    bool operator()(const _Tp& __x, const _Tp& __y) const
    { 
      return __x != __y; 
    }
  };


      template <class _Tp>
  struct greater : public binary_function<_Tp, _Tp, bool>
  {
    bool operator () (const _Tp& __x, const _Tp& __y) const
    { 
      return __x > __y; 
    }
  };


      template <class _Tp>
  struct less : public binary_function<_Tp, _Tp, bool>
  {
    bool operator () (const _Tp& __x, const _Tp& __y) const
    { 
      return __x < __y; 
    }
  };


      template <class _Tp>
  struct greater_equal : public binary_function<_Tp, _Tp, bool>
  {
    bool operator () (const _Tp& __x, const _Tp& __y) const
    { 
      return __x >= __y; 
    }
  };


      template <class _Tp>
  struct less_equal : public binary_function<_Tp, _Tp, bool>
  {
    bool operator () (const _Tp& __x, const _Tp& __y) const
    { 
      return __x <= __y; 
    }
  };


      template <class _Tp>
  struct logical_and : public binary_function<_Tp, _Tp, bool>
  {
    bool operator () (const _Tp& __x, const _Tp& __y) const
    { 
      return __x and __y; 
    }
  };


      template <class _Tp>
  struct logical_or : public binary_function<_Tp, _Tp, bool>
  {
    bool operator () (const _Tp& __x, const _Tp& __y) const
    { 
      return __x or __y; 
    }
  };


      template <class _Tp>
  struct logical_not : public unary_function<_Tp, bool>
  {
    bool operator () (const _Tp& __x) const
    { 
      return not __x; 
    }
  };


      template <class _Predicate>
  class unary_negate
    : public unary_function <typename _Predicate::argument_type, bool>
  {
    protected:

      _Predicate _M_pred;

    public:

    explicit unary_negate (const _Predicate& __x) : _M_pred(__x) {}

    bool operator () (const typename _Predicate::argument_type& __x) const
    { 
      return not _M_pred(__x); 
    }
  };


      template <class _Predicate> inline 
  unary_negate<_Predicate> not1 (const _Predicate& __pred)
  { 
    return unary_negate<_Predicate>(__pred); 
  }


      template <class _Predicate>
  class binary_negate
    : public binary_function<typename _Predicate::first_argument_type,
                             typename _Predicate::second_argument_type,
                             bool>
  {
  protected:

    _Predicate _M_pred;

  public:

    explicit binary_negate (const _Predicate& __x) : _M_pred(__x) { }

        bool 
    operator () (const typename _Predicate::first_argument_type& __x,
                 const typename _Predicate::second_argument_type& __y) const
      { 
        return not _M_pred(__x, __y); 
      }
  };


      template <class _Predicate> inline 
  binary_negate<_Predicate> not2 (const _Predicate& __pred)
  { 
    return binary_negate<_Predicate>(__pred); 
  }


      template <class _Operation>
  class binder1st
    : public unary_function<typename _Operation::second_argument_type,
                            typename _Operation::result_type>
  {
  protected:

    _Operation op;

    typename _Operation::first_argument_type value;

    public:
    
    binder1st(const _Operation& __x,
              const typename _Operation::first_argument_type& __y)
      : op(__x), value(__y) {}

        typename _Operation::result_type
    operator () (const typename _Operation::second_argument_type& __x) const
    { 
      return op (value, __x); 
    }

        typename _Operation::result_type
    operator () (typename _Operation::second_argument_type& __x) const
    { 
      return op(value, __x); 
    }
  };


      template <class _Operation, class _Tp> inline 
  binder1st<_Operation> bind1st(const _Operation& __fn, const _Tp& __x)
  {
    typedef typename _Operation::first_argument_type _Arg1_type;

    return binder1st<_Operation> (__fn, _Arg1_type(__x));
  }

      template <class _Operation>
  class binder2nd
    : public unary_function<typename _Operation::first_argument_type,
                            typename _Operation::result_type>
  {
  protected:

      _Operation op;

      typename _Operation::second_argument_type value;

    public:

    binder2nd(const _Operation& __x,
              const typename _Operation::second_argument_type& __y)
      : op(__x), value (__y) {}

        typename _Operation::result_type
    operator () (const typename _Operation::first_argument_type& __x) const
    { 
      return op (__x, value); 
    }
    
        typename _Operation::result_type
    operator () (typename _Operation::first_argument_type& __x) const
    { 
      return op (__x, value); 
    }
  };


      template <class _Operation, class _Tp> inline
  binder2nd<_Operation> bind2nd (const _Operation& __fn, const _Tp& __x)
  {
    typedef typename _Operation::second_argument_type _Arg2_type;

    return binder2nd<_Operation>(__fn, _Arg2_type(__x));
  }


      template <class _Arg, class _Result>
  class pointer_to_unary_function : public unary_function<_Arg, _Result>
  {
  protected:

    _Result (*_M_ptr) (_Arg);

  public:

    pointer_to_unary_function () {}

    explicit pointer_to_unary_function(_Result (*__x) (_Arg))
      : _M_ptr (__x) {}

    _Result operator () (_Arg __x) const
    {
      return _M_ptr (__x); 
    }
  };


      template <class _Arg, class _Result> inline 
  pointer_to_unary_function<_Arg, _Result> ptr_fun(_Result (*__x)(_Arg))
  { 
    return pointer_to_unary_function<_Arg, _Result>(__x); 
  }
  

      template <class _Arg1, class _Arg2, class _Result>
  class pointer_to_binary_function
    : public binary_function<_Arg1, _Arg2, _Result>
  {
  protected:

    _Result (*_M_ptr) (_Arg1, _Arg2);

  public:

    pointer_to_binary_function() {}

    explicit pointer_to_binary_function(_Result (*__x) (_Arg1, _Arg2))
      : _M_ptr(__x) {}

    _Result operator () (_Arg1 __x, _Arg2 __y) const
    {
      return _M_ptr(__x, __y); 
    }
  };


      template <class _Arg1, class _Arg2, class _Result> inline
  pointer_to_binary_function<_Arg1, _Arg2, _Result> 
  ptr_fun (_Result (*__x) (_Arg1, _Arg2) )
  {
    return pointer_to_binary_function<_Arg1, _Arg2, _Result>(__x); 
  }

      template <class _Tp>
  struct _Identity : public unary_function<_Tp,_Tp>
  {
    _Tp & operator () (_Tp& __x) const
    { 
      return __x;
    }

    const _Tp& operator () (const _Tp& __x) const
    { 
      return __x; 
    }
  };

      template <class _Pair> 
  struct _Select1st : public unary_function<_Pair, typename _Pair::first_type>
  {
    typename _Pair::first_type& operator () (_Pair& __x) const
    { 
      return __x.first; 
    }

    const typename _Pair::first_type& operator () (const _Pair& __x) const
    { 
      return __x.first; 
    }
  };

      template <class _Pair>
  struct _Select2nd : public unary_function<_Pair, typename _Pair::second_type>
  {
    typename _Pair::second_type& operator () (_Pair& __x) const
    {
      return __x.second; 
    }

    const typename _Pair::second_type& operator () (const _Pair& __x) const
    { 
      return __x.second; 
    }
  };


      template <class _Ret, class _Tp>
  class mem_fun_t : public unary_function<_Tp*, _Ret>
  {
  public:

    explicit mem_fun_t (_Ret (_Tp::*__pf) () )
      : _M_f(__pf) {}

    _Ret operator ()(_Tp* __p) const
    { 
      return (__p->*_M_f)(); 
    }

    private:

      _Ret (_Tp::*_M_f) ();
  };


      template <class _Ret, class _Tp>
  class const_mem_fun_t : public unary_function<const _Tp*, _Ret>
  {
  public:

    explicit const_mem_fun_t (_Ret (_Tp::*__pf) () const)
      : _M_f (__pf) {}

    _Ret operator () (const _Tp* __p) const
    { 
      return (__p->*_M_f) (); 
    }

    private:

    _Ret (_Tp::*_M_f) () const;
  };


      template <class _Ret, class _Tp>
  class mem_fun_ref_t : public unary_function<_Tp, _Ret>
  {
  public:

    explicit mem_fun_ref_t (_Ret (_Tp::*__pf)())
      : _M_f (__pf) {}

    _Ret operator () (_Tp& __r) const
    { 
      return (__r.*_M_f)(); 
    }

    private:

    _Ret (_Tp::*_M_f) ();
  };


      template <class _Ret, class _Tp>
  class const_mem_fun_ref_t : public unary_function<_Tp, _Ret>
  {
  public:

    explicit const_mem_fun_ref_t (_Ret (_Tp::*__pf)() const)
      : _M_f (__pf) {}

    _Ret operator () (const _Tp& __r) const
    { 
      return (__r.*_M_f)(); 
    }

    private:

    _Ret (_Tp::*_M_f) () const;
  };


      template <class _Ret, class _Tp, class _Arg>
  class mem_fun1_t : public binary_function<_Tp*, _Arg, _Ret>
  {
  public:

    explicit mem_fun1_t (_Ret (_Tp::*__pf) (_Arg))
      : _M_f(__pf) {}

    _Ret operator () (_Tp* __p, _Arg __x) const
    { 
      return (__p->*_M_f) (__x); 
    }

    private:
    
    _Ret (_Tp::*_M_f) (_Arg);
  };


      template <class _Ret, class _Tp, class _Arg>
  class const_mem_fun1_t : public binary_function<const _Tp*, _Arg, _Ret>
  {
  public:

    explicit const_mem_fun1_t (_Ret (_Tp::*__pf) (_Arg) const)
      : _M_f (__pf) {}

    _Ret operator () (const _Tp* __p, _Arg __x) const
    { 
      return (__p->*_M_f)(__x); 
    }

    private:

    _Ret (_Tp::*_M_f) (_Arg) const;
  };


      template <class _Ret, class _Tp, class _Arg>
  class mem_fun1_ref_t : public binary_function<_Tp, _Arg, _Ret>
  {
  public:
    
    explicit mem_fun1_ref_t (_Ret (_Tp::*__pf) (_Arg))
      : _M_f (__pf) {}

    _Ret operator () (_Tp& __r, _Arg __x) const
    { 
      return (__r.*_M_f)(__x); 
    }

    private:

    _Ret (_Tp::*_M_f) (_Arg);
  };


      template <class _Ret, class _Tp, class _Arg>
  class const_mem_fun1_ref_t : public binary_function<_Tp, _Arg, _Ret>
  {
  public:
  
    explicit const_mem_fun1_ref_t(_Ret (_Tp::*__pf)(_Arg) const)
      : _M_f(__pf) {}

    _Ret operator () (const _Tp& __r, _Arg __x) const
    { 
      return (__r.*_M_f)(__x); 
    }

    private:

      _Ret (_Tp::*_M_f) (_Arg) const;
  };


      template <class _Tp>
  class mem_fun_t<void, _Tp> : public unary_function<_Tp*, void>
  {
  public:
  
    explicit mem_fun_t (void (_Tp::*__pf)())
      : _M_f (__pf) {}

    void operator () (_Tp* __p) const
    {
      (__p->*_M_f)(); 
    }

    private:

    void (_Tp::*_M_f)();
  };


      template <class _Tp>
  class const_mem_fun_t<void, _Tp> : public unary_function<const _Tp*, void>
  {
  public:
  
    explicit const_mem_fun_t (void (_Tp::*__pf)() const)
      : _M_f (__pf) {}

    void operator () (const _Tp* __p) const
    { 
      (__p->*_M_f)(); 
    }

    private:

      void (_Tp::*_M_f)() const;
  };


      template <class _Tp>
  class mem_fun_ref_t<void, _Tp> : public unary_function<_Tp, void>
  {
  public:

    explicit mem_fun_ref_t (void (_Tp::*__pf)()) : _M_f (__pf) {}

    void operator () (_Tp& __r) const
    { 
      (__r.*_M_f)(); 
    }

    private:

      void (_Tp::*_M_f)();
  };


      template <class _Tp>
  class const_mem_fun_ref_t<void, _Tp> : public unary_function<_Tp, void>
  {
  public:

    explicit const_mem_fun_ref_t (void (_Tp::*__pf) () const)
      : _M_f (__pf) {}

    void operator () (const _Tp& __r) const
    {
      (__r.*_M_f) (); 
    }

    private:

    void (_Tp::*_M_f) () const;
  };


      template <class _Tp, class _Arg>
  class mem_fun1_t<void, _Tp, _Arg> : public binary_function<_Tp*, _Arg, void>
  {
  public:
    
    explicit mem_fun1_t(void (_Tp::*__pf) (_Arg)) : _M_f (__pf) {}

    void operator () (_Tp* __p, _Arg __x) const
    {
      (__p->*_M_f)(__x); 
    }

    private:

    void (_Tp::*_M_f) (_Arg);
  };


      template <class _Tp, class _Arg>
  class const_mem_fun1_t<void, _Tp, _Arg>
    : public binary_function<const _Tp*, _Arg, void>
  {
  public:

    explicit const_mem_fun1_t (void (_Tp::*__pf) (_Arg) const) : _M_f (__pf) {}

    void operator () (const _Tp* __p, _Arg __x) const
    { 
      (__p->*_M_f)(__x); 
    }

    private:

    void (_Tp::*_M_f)(_Arg) const;
  };


      template <class _Tp, class _Arg>
  class mem_fun1_ref_t<void, _Tp, _Arg>
    : public binary_function<_Tp, _Arg, void>
  {
  public:

    explicit mem_fun1_ref_t (void (_Tp::*__pf) (_Arg)) : _M_f (__pf) {}

    void operator () (_Tp& __r, _Arg __x) const
    { 
      (__r.*_M_f)(__x); 
    }

    private:

    void (_Tp::*_M_f) (_Arg);
  };


      template <class _Tp, class _Arg>
  class const_mem_fun1_ref_t<void, _Tp, _Arg>
    : public binary_function<_Tp, _Arg, void>
  {
  public:

    explicit const_mem_fun1_ref_t (void (_Tp::*__pf) (_Arg) const) 
      : _M_f (__pf) {}

    void operator () (const _Tp& __r, _Arg __x) const
    {
      (__r.*_M_f) (__x); 
    }

  private:

    void (_Tp::*_M_f)(_Arg) const;
  };


      template <class _Ret, class _Tp> inline
  mem_fun_t<_Ret, _Tp> mem_fun (_Ret (_Tp::*__f) () )
  {
    return mem_fun_t<_Ret, _Tp> (__f); 
  }

      template <class _Ret, class _Tp> inline 
  const_mem_fun_t<_Ret, _Tp> mem_fun (_Ret (_Tp::*__f) () const)
  { 
    return const_mem_fun_t<_Ret, _Tp> (__f); 
  }

      template <class _Ret, class _Tp> inline
  mem_fun_ref_t<_Ret, _Tp> mem_fun_ref (_Ret (_Tp::*__f) ())
  {
    return mem_fun_ref_t<_Ret, _Tp> (__f); 
  }

      template <class _Ret, class _Tp> inline 
  const_mem_fun_ref_t<_Ret, _Tp> mem_fun_ref (_Ret (_Tp::*__f) () const)
  { 
    return const_mem_fun_ref_t<_Ret, _Tp> (__f); 
  }

      template <class _Ret, class _Tp, class _Arg> inline
  mem_fun1_t<_Ret, _Tp, _Arg> mem_fun (_Ret (_Tp::*__f) (_Arg))
  {
    return mem_fun1_t<_Ret, _Tp, _Arg> (__f); 
  }

      template <class _Ret, class _Tp, class _Arg> inline
  const_mem_fun1_t<_Ret, _Tp, _Arg> mem_fun (_Ret (_Tp::*__f) (_Arg) const)
  { 
    return const_mem_fun1_t<_Ret, _Tp, _Arg>(__f); 
  }

      template <class _Ret, class _Tp, class _Arg> inline
  mem_fun1_ref_t<_Ret, _Tp, _Arg> mem_fun_ref (_Ret (_Tp::*__f) (_Arg))
  { 
    return mem_fun1_ref_t<_Ret, _Tp, _Arg>(__f); 
  }

      template <class _Ret, class _Tp, class _Arg> inline
  const_mem_fun1_ref_t<_Ret, _Tp, _Arg> 
      mem_fun_ref (_Ret (_Tp::*__f) (_Arg) const)
  { 
    return const_mem_fun1_ref_t<_Ret, _Tp, _Arg>(__f); 
  }


    template <class T, class Compare> inline
bool less_than(const T & op1, const T & op2, Compare & cmp)
{
  return cmp (op1, op2);
}

 
    template <class T, class Compare> inline
bool less_than(const T & op1, const T & op2, Compare && cmp = Compare())
{
  return less_than <T, Compare> (op1, op2, cmp);
}


    template <class T, class Compare> inline
bool less_or_equal_than(const T& op1, const T& op2, Compare & cmp)
{
  if (cmp(op1, op2))
    return true;
  
  if (cmp(op2, op1))
    return false;

  return true;
}


    template <class T, class Compare> inline
bool less_or_equal_than(const T& op1, const T& op2, Compare && cmp = Compare())
{
  return less_or_equal_than<T, Compare>(op1, op2, cmp);
}


    template <class T, class Compare> inline
bool greater_than(const T& op1, const T& op2, Compare && cmp = Compare())
{
  return not less_or_equal_than<T, Compare> (op1, op2, std::move(cmp));
}

  template <class T, class Compare> inline
bool greater_than(const T& op1, const T& op2, Compare & cmp)
{
  return not less_or_equal_than<T, Compare> (op1, op2, cmp);
}

    template <class T, class Compare> inline
bool greater_or_equal_than(const T& op1, const T & op2, 
                           Compare && cmp = Compare())
{
  return not less_than<T, Compare> (op1, op2, std::move(cmp));
}

    template <class T, class Compare> inline
bool greater_or_equal_than(const T& op1, const T& op2, Compare & cmp)
{
  return not less_than<T, Compare> (op1, op2, cmp);
}

    template <class T, class Compare> inline
bool no_equals(const T & op1, const T & op2, Compare && cmp = Compare())
{
  return cmp(op1, op2) or cmp(op2, op1);
}

    template <class T, class Compare> inline
bool no_equals(const T & op1, const T & op2, Compare & cmp)
{
  return cmp(op1, op2) or cmp(op2, op1);
}

    template <class T, class Compare> inline
bool are_equals(const T & op1, const T & op2, Compare && cmp = Compare())
{
  return not no_equals <T, Compare> (op1, op2, std::move(cmp));
}

    template <class T, class Compare> inline
bool are_equals(const T & op1, const T & op2, Compare & cmp)
{
  return not no_equals <T, Compare> (op1, op2, cmp);
}

    template <class T, class Compare>
struct Inversed_Compare
{
  bool operator () (const T & op1, const T & op2) const
  {
    return Compare () (op2, op1);
  }
};

    template <class T, class Compare>
struct Compare_Dup 
{
  bool operator () (const T & op1, const T & op2) const
  {
    if (Compare () (op1, op2))
      return true;
    
    if (Compare () (op2, op1))
      return false;

    return true; 
  }
};

} // namespace Aleph

#endif /* AHFUNCTION_H */