gcc/libstdc++-v3/include/bits/stl_map.h

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C++

// Map implementation -*- C++ -*-
// Copyright (C) 2001, 2002 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 2, 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 General Public License for more details.
// You should have received a copy of the GNU General Public License along
// with this library; see the file COPYING. If not, write to the Free
// Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
// USA.
// As a special exception, you may use this file as part of a free software
// library without restriction. Specifically, if other files instantiate
// templates or use macros or inline functions from this file, or you compile
// this file and link it with other files to produce an executable, this
// file does not by itself cause the resulting executable to be covered by
// the GNU General Public License. This exception does not however
// invalidate any other reasons why the executable file might be covered by
// the GNU General Public License.
/*
*
* 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) 1996,1997
* 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.
*/
/** @file stl_map.h
* This is an internal header file, included by other library headers.
* You should not attempt to use it directly.
*/
#ifndef _CPP_BITS_STL_MAP_H
#define _CPP_BITS_STL_MAP_H 1
#include <bits/concept_check.h>
namespace std
{
/**
* @brief A standard container made up of pairs (see std::pair in <utility>)
* which can be retrieved based on a key.
*
* This is an associative container. Values contained within it can be
* quickly retrieved through a key element. Example: MyMap["First"] would
* return the data associated with the key "First".
*/
template <class _Key, class _Tp, class _Compare = less<_Key>,
class _Alloc = allocator<pair<const _Key, _Tp> > >
class map
{
// concept requirements
__glibcpp_class_requires(_Tp, _SGIAssignableConcept)
__glibcpp_class_requires4(_Compare, bool, _Key, _Key, _BinaryFunctionConcept);
public:
// typedefs:
typedef _Key key_type;
typedef _Tp data_type;
typedef _Tp mapped_type;
typedef pair<const _Key, _Tp> value_type;
typedef _Compare key_compare;
class value_compare
: public binary_function<value_type, value_type, bool> {
friend class map<_Key,_Tp,_Compare,_Alloc>;
protected :
_Compare comp;
value_compare(_Compare __c) : comp(__c) {}
public:
bool operator()(const value_type& __x, const value_type& __y) const {
return comp(__x.first, __y.first);
}
};
private:
typedef _Rb_tree<key_type, value_type,
_Select1st<value_type>, key_compare, _Alloc> _Rep_type;
_Rep_type _M_t; // red-black tree representing map
public:
typedef typename _Rep_type::pointer pointer;
typedef typename _Rep_type::const_pointer const_pointer;
typedef typename _Rep_type::reference reference;
typedef typename _Rep_type::const_reference const_reference;
typedef typename _Rep_type::iterator iterator;
typedef typename _Rep_type::const_iterator const_iterator;
typedef typename _Rep_type::reverse_iterator reverse_iterator;
typedef typename _Rep_type::const_reverse_iterator const_reverse_iterator;
typedef typename _Rep_type::size_type size_type;
typedef typename _Rep_type::difference_type difference_type;
typedef typename _Rep_type::allocator_type allocator_type;
// allocation/deallocation
map() : _M_t(_Compare(), allocator_type()) {}
explicit map(const _Compare& __comp,
const allocator_type& __a = allocator_type())
: _M_t(__comp, __a) {}
template <class _InputIterator>
map(_InputIterator __first, _InputIterator __last)
: _M_t(_Compare(), allocator_type())
{ _M_t.insert_unique(__first, __last); }
template <class _InputIterator>
map(_InputIterator __first, _InputIterator __last, const _Compare& __comp,
const allocator_type& __a = allocator_type())
: _M_t(__comp, __a) { _M_t.insert_unique(__first, __last); }
map(const map<_Key,_Tp,_Compare,_Alloc>& __x) : _M_t(__x._M_t) {}
map<_Key,_Tp,_Compare,_Alloc>&
operator=(const map<_Key, _Tp, _Compare, _Alloc>& __x)
{
_M_t = __x._M_t;
return *this;
}
// accessors:
key_compare key_comp() const { return _M_t.key_comp(); }
value_compare value_comp() const { return value_compare(_M_t.key_comp()); }
allocator_type get_allocator() const { return _M_t.get_allocator(); }
/**
* Returns a read/write iterator that points to the first pair in the map.
* Iteration is done in ascending order according to the keys.
*/
iterator begin() { return _M_t.begin(); }
/**
* Returns a read-only (constant) iterator that points to the first pair
* in the map. Iteration is done in ascending order according to the keys.
*/
const_iterator begin() const { return _M_t.begin(); }
/**
* Returns a read/write iterator that points one past the last pair in the
* map. Iteration is done in ascending order according to the keys.
*/
iterator end() { return _M_t.end(); }
/**
* Returns a read-only (constant) iterator that points one past the last
* pair in the map. Iteration is done in ascending order according to the
* keys.
*/
const_iterator end() const { return _M_t.end(); }
/**
* Returns a read/write reverse iterator that points to the last pair in
* the map. Iteration is done in descending order according to the keys.
*/
reverse_iterator rbegin() { return _M_t.rbegin(); }
/**
* Returns a read-only (constant) reverse iterator that points to the last
* pair in the map. Iteration is done in descending order according to
* the keys.
*/
const_reverse_iterator rbegin() const { return _M_t.rbegin(); }
/**
* Returns a read/write reverse iterator that points to one before the
* first pair in the map. Iteration is done in descending order according
* to the keys.
*/
reverse_iterator rend() { return _M_t.rend(); }
/**
* Returns a read-only (constant) reverse iterator that points to one
* before the first pair in the map. Iteration is done in descending order
* according to the keys.
*/
const_reverse_iterator rend() const { return _M_t.rend(); }
/** Returns true if the map is empty. (Thus begin() would equal end().) */
bool empty() const { return _M_t.empty(); }
/** Returns the size of the map. */
size_type size() const { return _M_t.size(); }
/** Returns the maximum size of the map. */
size_type max_size() const { return _M_t.max_size(); }
/**
* @brief Subscript ( [] ) access to map data.
* @param k The key for which data should be retrieved.
*
* Allows for easy lookup with the subscript ( [] ) operator. Returns the
* data associated with the key specified in subscript. If the key does
* not exist a pair with that key is created with a default value, which
* is then returned.
*/
_Tp& operator[](const key_type& __k) {
iterator __i = lower_bound(__k);
// __i->first is greater than or equivalent to __k.
if (__i == end() || key_comp()(__k, (*__i).first))
__i = insert(__i, value_type(__k, _Tp()));
return (*__i).second;
}
void swap(map<_Key,_Tp,_Compare,_Alloc>& __x) { _M_t.swap(__x._M_t); }
// insert/erase
/**
* @brief Attempts to insert a std::pair into the map.
* @param x Pair to be inserted (see std::make_pair for easy creation of
* pairs).
* @return A pair of which the first element is an iterator that points
* to the possibly inserted pair, a second element of type bool
* to show if the pair was actually inserted.
*
* This function attempts to insert a (key, value) pair into the map. A
* map relies on unique keys and thus a pair is only inserted if its first
* element (the key) is not already present in the map.
*/
pair<iterator,bool> insert(const value_type& __x)
{ return _M_t.insert_unique(__x); }
/**
* @brief Attempts to insert a std::pair into the map.
* @param position An iterator that serves as a hint as to where the
* pair should be inserted.
* @param x Pair to be inserted (see std::make_pair for easy creation of
* pairs).
* @return An iterator that points to the inserted (key,value) pair.
*
* This function is not concerned about whether the insertion took place
* or not and thus does not return a boolean like the single-argument
* insert() does. Note that the first parameter is only a hint and can
* potentially improve the performance of the insertion process. A bad
* hint would cause no gains in efficiency.
*/
iterator insert(iterator position, const value_type& __x)
{ return _M_t.insert_unique(position, __x); }
/**
* @brief A template function that attemps to insert elements from
* another range (possibly another map).
* @param first Iterator pointing to the start of the range to be inserted.
* @param last Iterator pointing to the end of the range.
*/
template <class _InputIterator>
void insert(_InputIterator __first, _InputIterator __last) {
_M_t.insert_unique(__first, __last);
}
/**
* @brief Erases an element from a map.
* @param position An iterator pointing to the element to be erased.
*
* This function erases an element, pointed to by the given iterator, from
* a map. Note that this function only erases the element, and that if
* the element is itself a pointer, the pointed-to memory is not touched
* in any way. Managing the pointer is the user's responsibilty.
*/
void erase(iterator __position) { _M_t.erase(__position); }
/**
* @brief Erases an element according to the provided key.
* @param x Key of element to be erased.
* @return Doc me! (Number of elements that match key? Only makes sense
* with multimap)
*
* This function erases an element, located by the given key, from a map.
* Note that this function only erases the element, and that if
* the element is itself a pointer, the pointed-to memory is not touched
* in any way. Managing the pointer is the user's responsibilty.
*/
size_type erase(const key_type& __x) { return _M_t.erase(__x); }
/**
* @brief Erases a [first,last) range of elements from a map.
* @param first Iterator pointing to the start of the range to be erased.
* @param last Iterator pointing to the end of the range to be erased.
*
* This function erases a sequence of elements from a map.
* Note that this function only erases the element, and that if
* the element is itself a pointer, the pointed-to memory is not touched
* in any way. Managing the pointer is the user's responsibilty.
*/
void erase(iterator __first, iterator __last)
{ _M_t.erase(__first, __last); }
/** Erases all elements in a map. Note that this function only erases
* the elements, and that if the elements themselves are pointers, the
* pointed-to memory is not touched in any way. Managing the pointer is
* the user's responsibilty.
*/
void clear() { _M_t.clear(); }
// map operations:
/**
* @brief Tries to locate an element in a map.
* @param x Key of (key, value) pair to be located.
* @return Iterator pointing to sought-after element, or end() if not
* found.
*
* This function takes a key and tries to locate the element with which
* the key matches. If successful the function returns an iterator
* pointing to the sought after pair. If unsuccessful it returns the
* one past the end ( end() ) iterator.
*/
iterator find(const key_type& __x) { return _M_t.find(__x); }
/**
* @brief Tries to locate an element in a map.
* @param x Key of (key, value) pair to be located.
* @return Read-only (constant) iterator pointing to sought-after
* element, or end() if not found.
*
* This function takes a key and tries to locate the element with which
* the key matches. If successful the function returns a constant iterator
* pointing to the sought after pair. If unsuccessful it returns the
* one past the end ( end() ) iterator.
*/
const_iterator find(const key_type& __x) const { return _M_t.find(__x); }
/**
* @brief Finds the number of elements with given key.
* @param x Key of (key, value) pairs to be located.
* @return Number of elements with specified key.
*
* This function only makes sense for multimaps.
*/
size_type count(const key_type& __x) const {
return _M_t.find(__x) == _M_t.end() ? 0 : 1;
}
/**
* @brief Finds the beginning of a subsequence matching given key.
* @param x Key of (key, value) pair to be located.
* @return Iterator pointing to first element matching given key, or
* end() if not found.
*
* This function is useful only with std::multimap. It returns the first
* element of a subsequence of elements that matches the given key. If
* unsuccessful it returns an iterator pointing to the first element that
* has a greater value than given key or end() if no such element exists.
*/
iterator lower_bound(const key_type& __x) {return _M_t.lower_bound(__x); }
/**
* @brief Finds the beginning of a subsequence matching given key.
* @param x Key of (key, value) pair to be located.
* @return Read-only (constant) iterator pointing to first element
* matching given key, or end() if not found.
*
* This function is useful only with std::multimap. It returns the first
* element of a subsequence of elements that matches the given key. If
* unsuccessful the iterator will point to the next greatest element or,
* if no such greater element exists, to end().
*/
const_iterator lower_bound(const key_type& __x) const {
return _M_t.lower_bound(__x);
}
/**
* @brief Finds the end of a subsequence matching given key.
* @param x Key of (key, value) pair to be located.
* @return Iterator pointing to last element matching given key.
*
* This function only makes sense with multimaps.
*/
iterator upper_bound(const key_type& __x) {return _M_t.upper_bound(__x); }
/**
* @brief Finds the end of a subsequence matching given key.
* @param x Key of (key, value) pair to be located.
* @return Read-only (constant) iterator pointing to last element matching
* given key.
*
* This function only makes sense with multimaps.
*/
const_iterator upper_bound(const key_type& __x) const {
return _M_t.upper_bound(__x);
}
/**
* @brief Finds a subsequence matching given key.
* @param x Key of (key, value) pairs to be located.
* @return Pair of iterators that possibly points to the subsequence
* matching given key.
*
* This function improves on lower_bound() and upper_bound() by giving a more
* elegant and efficient solution. It returns a pair of which the first
* element possibly points to the first element matching the given key
* and the second element possibly points to the last element matching the
* given key. If unsuccessful the first element of the returned pair will
* contain an iterator pointing to the next greatest element or, if no such
* greater element exists, to end().
*
* This function only makes sense for multimaps.
*/
pair<iterator,iterator> equal_range(const key_type& __x) {
return _M_t.equal_range(__x);
}
/**
* @brief Finds a subsequence matching given key.
* @param x Key of (key, value) pairs to be located.
* @return Pair of read-only (constant) iterators that possibly points to
* the subsequence matching given key.
*
* This function improves on lower_bound() and upper_bound() by giving a more
* elegant and efficient solution. It returns a pair of which the first
* element possibly points to the first element matching the given key
* and the second element possibly points to the last element matching the
* given key. If unsuccessful the first element of the returned pair will
* contain an iterator pointing to the next greatest element or, if no such
* a greater element exists, to end().
*
* This function only makes sense for multimaps.
*/
pair<const_iterator,const_iterator> equal_range(const key_type& __x) const {
return _M_t.equal_range(__x);
}
template <class _K1, class _T1, class _C1, class _A1>
friend bool operator== (const map<_K1, _T1, _C1, _A1>&,
const map<_K1, _T1, _C1, _A1>&);
template <class _K1, class _T1, class _C1, class _A1>
friend bool operator< (const map<_K1, _T1, _C1, _A1>&,
const map<_K1, _T1, _C1, _A1>&);
};
template <class _Key, class _Tp, class _Compare, class _Alloc>
inline bool operator==(const map<_Key,_Tp,_Compare,_Alloc>& __x,
const map<_Key,_Tp,_Compare,_Alloc>& __y) {
return __x._M_t == __y._M_t;
}
template <class _Key, class _Tp, class _Compare, class _Alloc>
inline bool operator<(const map<_Key,_Tp,_Compare,_Alloc>& __x,
const map<_Key,_Tp,_Compare,_Alloc>& __y) {
return __x._M_t < __y._M_t;
}
template <class _Key, class _Tp, class _Compare, class _Alloc>
inline bool operator!=(const map<_Key,_Tp,_Compare,_Alloc>& __x,
const map<_Key,_Tp,_Compare,_Alloc>& __y) {
return !(__x == __y);
}
template <class _Key, class _Tp, class _Compare, class _Alloc>
inline bool operator>(const map<_Key,_Tp,_Compare,_Alloc>& __x,
const map<_Key,_Tp,_Compare,_Alloc>& __y) {
return __y < __x;
}
template <class _Key, class _Tp, class _Compare, class _Alloc>
inline bool operator<=(const map<_Key,_Tp,_Compare,_Alloc>& __x,
const map<_Key,_Tp,_Compare,_Alloc>& __y) {
return !(__y < __x);
}
template <class _Key, class _Tp, class _Compare, class _Alloc>
inline bool operator>=(const map<_Key,_Tp,_Compare,_Alloc>& __x,
const map<_Key,_Tp,_Compare,_Alloc>& __y) {
return !(__x < __y);
}
template <class _Key, class _Tp, class _Compare, class _Alloc>
inline void swap(map<_Key,_Tp,_Compare,_Alloc>& __x,
map<_Key,_Tp,_Compare,_Alloc>& __y) {
__x.swap(__y);
}
} // namespace std
#endif /* _CPP_BITS_STL_MAP_H */
// Local Variables:
// mode:C++
// End: