_function.h

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/*
 *
 * Copyright (c) 1994
 * Hewlett-Packard Company
 *
 * Copyright (c) 1996-1998
 * Silicon Graphics Computer Systems, Inc.
 *
 * Copyright (c) 1997
 * Moscow Center for SPARC Technology
 *
 * Copyright (c) 1999
 * Boris Fomitchev
 *
 * This material is provided "as is", with absolutely no warranty expressed
 * or implied. Any use is at your own risk.
 *
 * Permission to use or copy this software for any purpose is hereby granted
 * without fee, provided the above notices are retained on all copies.
 * Permission to modify the code and to distribute modified code is granted,
 * provided the above notices are retained, and a notice that the code was
 * modified is included with the above copyright notice.
 *
 */

/* NOTE: This is an internal header file, included by other STL headers.
 *   You should not attempt to use it directly.
 */

#ifndef _STLP_INTERNAL_FUNCTION_H
#define _STLP_INTERNAL_FUNCTION_H

#ifndef _STLP_TYPE_TRAITS_H
#  include <stl/type_traits.h>
#endif

#ifndef _STLP_INTERNAL_FUNCTION_BASE_H
#  include <stl/_function_base.h>
#endif

_STLP_BEGIN_NAMESPACE

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

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

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

#if !defined (_STLP_NO_EXTENSIONS)
// identity_element (not part of the C++ standard).
template <class _Tp> inline _Tp identity_element(plus<_Tp>) {  return _Tp(0); }
template <class _Tp> inline _Tp identity_element(multiplies<_Tp>) { return _Tp(1); }
#endif

#if defined (_STLP_BASE_TYPEDEF_BUG)
// this workaround is needed for SunPro 4.0.1
// suggested by "Martin Abernethy" <[e-mail]>:

// We have to introduce the XXary_predicate_aux structures in order to
// access the argument and return types of predicate functions supplied
// as type parameters. SUN C++ 4.0.1 compiler gives errors for template type parameters
// of the form 'name1::name2', where name1 is itself a type parameter.
template <class _Pair>
struct __pair_aux : private _Pair {
  typedef typename _Pair::first_type first_type;
  typedef typename _Pair::second_type second_type;
};

template <class _Operation>
struct __unary_fun_aux : private _Operation {
  typedef typename _Operation::argument_type argument_type;
  typedef typename _Operation::result_type result_type;
};

template <class _Operation>
struct __binary_fun_aux  : private _Operation {
  typedef typename _Operation::first_argument_type first_argument_type;
  typedef typename _Operation::second_argument_type second_argument_type;
  typedef typename _Operation::result_type result_type;
};

#  define __UNARY_ARG(__Operation,__type)  __unary_fun_aux<__Operation>::__type
#  define __BINARY_ARG(__Operation,__type)  __binary_fun_aux<__Operation>::__type
#  define __PAIR_ARG(__Pair,__type)  __pair_aux<__Pair>::__type
#else
#  define __UNARY_ARG(__Operation,__type)  __Operation::__type
#  define __BINARY_ARG(__Operation,__type) __Operation::__type
#  define __PAIR_ARG(__Pair,__type) __Pair::__type
#endif

template <class _Predicate>
class unary_negate
    : public unary_function<typename __UNARY_ARG(_Predicate, argument_type), bool> {
  typedef unary_function<typename __UNARY_ARG(_Predicate, argument_type), bool> _Base;
public:
  typedef typename _Base::argument_type argument_type;
private:
  typedef typename __call_traits<argument_type>::const_param_type _ArgParamType;
protected:
  _Predicate _M_pred;
public:
  explicit unary_negate(const _Predicate& __x) : _M_pred(__x) {}
  bool operator()(_ArgParamType __x) const {
    return !_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 __BINARY_ARG(_Predicate, first_argument_type),
                             typename __BINARY_ARG(_Predicate, second_argument_type),
                             bool> {
  typedef binary_function<typename __BINARY_ARG(_Predicate, first_argument_type),
                          typename __BINARY_ARG(_Predicate, second_argument_type),
                          bool> _Base;
public:
  typedef typename _Base::first_argument_type first_argument_type;
  typedef typename _Base::second_argument_type second_argument_type;
private:
  typedef typename __call_traits<first_argument_type>::const_param_type _FstArgParamType;
  typedef typename __call_traits<second_argument_type>::const_param_type _SndArgParamType;
protected:
  _Predicate _M_pred;
public:
  explicit binary_negate(const _Predicate& __x) : _M_pred(__x) {}
  bool operator()(_FstArgParamType __x, _SndArgParamType __y) const {
    return !_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 __BINARY_ARG(_Operation, second_argument_type),
                          typename __BINARY_ARG(_Operation, result_type) > {
  typedef unary_function<typename __BINARY_ARG(_Operation, second_argument_type),
                         typename __BINARY_ARG(_Operation, result_type) > _Base;
public:
  typedef typename _Base::argument_type argument_type;
  typedef typename _Base::result_type result_type;
private:
  typedef typename __call_traits<argument_type>::param_type _ArgParamType;
  typedef typename __call_traits<argument_type>::const_param_type _ConstArgParamType;
  typedef typename __call_traits<typename _Operation::first_argument_type>::const_param_type _ValueParamType;
protected:
  //op is a Standard name (20.3.6.1), do no make it STLport naming convention compliant.
  _Operation op;
  typename _Operation::first_argument_type _M_value;
public:
  binder1st(const _Operation& __x, _ValueParamType __y)
    : op(__x), _M_value(__y) {}

  result_type operator()(_ConstArgParamType __x) const
  { return op(_M_value, __x); }
  // DR 109 Missing binders for non-const sequence elements
  result_type operator()(_ArgParamType __x) const
  { return op(_M_value, __x); }
};

template <class _Operation, class _Tp>
inline binder1st<_Operation>
bind1st(const _Operation& __fn, const _Tp& __x) {