| // Map implementation -*- C++ -*- |
| |
| // Copyright (C) 2001, 2002, 2004, 2005 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 _MAP_H |
| #define _MAP_H 1 |
| |
| #include <bits/concept_check.h> |
| |
| namespace _GLIBCXX_STD |
| { |
| /** |
| * @brief A standard container made up of (key,value) pairs, which can be |
| * retrieved based on a key, in logarithmic time. |
| * |
| * @ingroup Containers |
| * @ingroup Assoc_containers |
| * |
| * Meets the requirements of a <a href="tables.html#65">container</a>, a |
| * <a href="tables.html#66">reversible container</a>, and an |
| * <a href="tables.html#69">associative container</a> (using unique keys). |
| * For a @c map<Key,T> the key_type is Key, the mapped_type is T, and the |
| * value_type is std::pair<const Key,T>. |
| * |
| * Maps support bidirectional iterators. |
| * |
| * @if maint |
| * The private tree data is declared exactly the same way for map and |
| * multimap; the distinction is made entirely in how the tree functions are |
| * called (*_unique versus *_equal, same as the standard). |
| * @endif |
| */ |
| template <typename _Key, typename _Tp, typename _Compare = std::less<_Key>, |
| typename _Alloc = std::allocator<std::pair<const _Key, _Tp> > > |
| class map |
| { |
| // concept requirements |
| __glibcxx_class_requires(_Tp, _SGIAssignableConcept) |
| __glibcxx_class_requires4(_Compare, bool, _Key, _Key, |
| _BinaryFunctionConcept) |
| |
| public: |
| typedef _Key key_type; |
| typedef _Tp mapped_type; |
| typedef std::pair<const _Key, _Tp> value_type; |
| typedef _Compare key_compare; |
| |
| class value_compare |
| : public std::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: |
| /// @if maint This turns a red-black tree into a [multi]map. @endif |
| typedef _Rb_tree<key_type, value_type, |
| _Select1st<value_type>, key_compare, _Alloc> _Rep_type; |
| /// @if maint The actual tree structure. @endif |
| _Rep_type _M_t; |
| |
| public: |
| // many of these are specified differently in ISO, but the following are |
| // "functionally equivalent" |
| typedef typename _Alloc::pointer pointer; |
| typedef typename _Alloc::const_pointer const_pointer; |
| typedef typename _Alloc::reference reference; |
| typedef typename _Alloc::const_reference const_reference; |
| typedef typename _Rep_type::allocator_type allocator_type; |
| typedef typename _Rep_type::iterator iterator; |
| typedef typename _Rep_type::const_iterator const_iterator; |
| typedef typename _Rep_type::size_type size_type; |
| typedef typename _Rep_type::difference_type difference_type; |
| typedef typename _Rep_type::reverse_iterator reverse_iterator; |
| typedef typename _Rep_type::const_reverse_iterator const_reverse_iterator; |
| |
| // [23.3.1.1] construct/copy/destroy |
| // (get_allocator() is normally listed in this section, but seems to have |
| // been accidentally omitted in the printed standard) |
| /** |
| * @brief Default constructor creates no elements. |
| */ |
| map() |
| : _M_t(_Compare(), allocator_type()) { } |
| |
| // for some reason this was made a separate function |
| /** |
| * @brief Default constructor creates no elements. |
| */ |
| explicit |
| map(const _Compare& __comp, const allocator_type& __a = allocator_type()) |
| : _M_t(__comp, __a) { } |
| |
| /** |
| * @brief Map copy constructor. |
| * @param x A %map of identical element and allocator types. |
| * |
| * The newly-created %map uses a copy of the allocation object used |
| * by @a x. |
| */ |
| map(const map& __x) |
| : _M_t(__x._M_t) { } |
| |
| /** |
| * @brief Builds a %map from a range. |
| * @param first An input iterator. |
| * @param last An input iterator. |
| * |
| * Create a %map consisting of copies of the elements from [first,last). |
| * This is linear in N if the range is already sorted, and NlogN |
| * otherwise (where N is distance(first,last)). |
| */ |
| template <typename _InputIterator> |
| map(_InputIterator __first, _InputIterator __last) |
| : _M_t(_Compare(), allocator_type()) |
| { _M_t.insert_unique(__first, __last); } |
| |
| /** |
| * @brief Builds a %map from a range. |
| * @param first An input iterator. |
| * @param last An input iterator. |
| * @param comp A comparison functor. |
| * @param a An allocator object. |
| * |
| * Create a %map consisting of copies of the elements from [first,last). |
| * This is linear in N if the range is already sorted, and NlogN |
| * otherwise (where N is distance(first,last)). |
| */ |
| template <typename _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); } |
| |
| // FIXME There is no dtor declared, but we should have something generated |
| // by Doxygen. I don't know what tags to add to this paragraph to make |
| // that happen: |
| /** |
| * The dtor only erases the elements, and note 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. |
| */ |
| |
| /** |
| * @brief Map assignment operator. |
| * @param x A %map of identical element and allocator types. |
| * |
| * All the elements of @a x are copied, but unlike the copy constructor, |
| * the allocator object is not copied. |
| */ |
| map& |
| operator=(const map& __x) |
| { |
| _M_t = __x._M_t; |
| return *this; |
| } |
| |
| /// Get a copy of the memory allocation object. |
| allocator_type |
| get_allocator() const |
| { return _M_t.get_allocator(); } |
| |
| // iterators |
| /** |
| * 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(); } |
| |
| // capacity |
| /** 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(); } |
| |
| // [23.3.1.2] element access |
| /** |
| * @brief Subscript ( @c [] ) access to %map data. |
| * @param k The key for which data should be retrieved. |
| * @return A reference to the data of the (key,data) %pair. |
| * |
| * Allows for easy lookup with the subscript ( @c [] ) operator. Returns |
| * data associated with the key specified in subscript. If the key does |
| * not exist, a pair with that key is created using default values, which |
| * is then returned. |
| * |
| * Lookup requires logarithmic time. |
| */ |
| mapped_type& |
| operator[](const key_type& __k) |
| { |
| // concept requirements |
| __glibcxx_function_requires(_DefaultConstructibleConcept<mapped_type>) |
| |
| 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, mapped_type())); |
| return (*__i).second; |
| } |
| |
| // modifiers |
| /** |
| * @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, and the second is a bool that |
| * is true 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. |
| * |
| * Insertion requires logarithmic time. |
| */ |
| std::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 element with key of @a x (may |
| * or may not be the %pair passed in). |
| * |
| * This function is not concerned about whether the insertion took place, |
| * 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. |
| * |
| * See http://gcc.gnu.org/onlinedocs/libstdc++/23_containers/howto.html#4 |
| * for more on "hinting". |
| * |
| * Insertion requires logarithmic time (if the hint is not taken). |
| */ |
| iterator |
| insert(iterator position, const value_type& __x) |
| { return _M_t.insert_unique(position, __x); } |
| |
| /** |
| * @brief A template function that attemps to insert a range of elements. |
| * @param first Iterator pointing to the start of the range to be |
| * inserted. |
| * @param last Iterator pointing to the end of the range. |
| * |
| * Complexity similar to that of the range constructor. |
| */ |
| template <typename _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 elements according to the provided key. |
| * @param x Key of element to be erased. |
| * @return The number of elements erased. |
| * |
| * This function erases all the elements 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); } |
| |
| /** |
| * @brief Swaps data with another %map. |
| * @param x A %map of the same element and allocator types. |
| * |
| * This exchanges the elements between two maps in constant time. |
| * (It is only swapping a pointer, an integer, and an instance of |
| * the @c Compare type (which itself is often stateless and empty), so it |
| * should be quite fast.) |
| * Note that the global std::swap() function is specialized such that |
| * std::swap(m1,m2) will feed to this function. |
| */ |
| void |
| swap(map& __x) |
| { _M_t.swap(__x._M_t); } |
| |
| /** |
| * 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(); } |
| |
| // observers |
| /** |
| * Returns the key comparison object out of which the %map was |
| * constructed. |
| */ |
| key_compare |
| key_comp() const |
| { return _M_t.key_comp(); } |
| |
| /** |
| * Returns a value comparison object, built from the key comparison |
| * object out of which the %map was constructed. |
| */ |
| value_compare |
| value_comp() const |
| { return value_compare(_M_t.key_comp()); } |
| |
| // [23.3.1.3] 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 |
| * past-the-end ( @c 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 past-the-end ( @c 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; for map the result will |
| * either be 0 (not present) or 1 (present). |
| */ |
| 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 equal to or greater |
| * than key, or end(). |
| * |
| * This function 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 |
| * equal to or greater than key, or end(). |
| * |
| * This function 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. |
| */ |
| 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 the first element |
| * greater than key, or end(). |
| */ |
| 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 first iterator |
| * greater than key, or end(). |
| */ |
| 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 is equivalent to |
| * @code |
| * std::make_pair(c.lower_bound(val), |
| * c.upper_bound(val)) |
| * @endcode |
| * (but is faster than making the calls separately). |
| * |
| * This function probably only makes sense for multimaps. |
| */ |
| std::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 is equivalent to |
| * @code |
| * std::make_pair(c.lower_bound(val), |
| * c.upper_bound(val)) |
| * @endcode |
| * (but is faster than making the calls separately). |
| * |
| * This function probably only makes sense for multimaps. |
| */ |
| std::pair<const_iterator,const_iterator> |
| equal_range(const key_type& __x) const |
| { return _M_t.equal_range(__x); } |
| |
| template <typename _K1, typename _T1, typename _C1, typename _A1> |
| friend bool |
| operator== (const map<_K1,_T1,_C1,_A1>&, |
| const map<_K1,_T1,_C1,_A1>&); |
| |
| template <typename _K1, typename _T1, typename _C1, typename _A1> |
| friend bool |
| operator< (const map<_K1,_T1,_C1,_A1>&, |
| const map<_K1,_T1,_C1,_A1>&); |
| }; |
| |
| /** |
| * @brief Map equality comparison. |
| * @param x A %map. |
| * @param y A %map of the same type as @a x. |
| * @return True iff the size and elements of the maps are equal. |
| * |
| * This is an equivalence relation. It is linear in the size of the |
| * maps. Maps are considered equivalent if their sizes are equal, |
| * and if corresponding elements compare equal. |
| */ |
| template <typename _Key, typename _Tp, typename _Compare, typename _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; } |
| |
| /** |
| * @brief Map ordering relation. |
| * @param x A %map. |
| * @param y A %map of the same type as @a x. |
| * @return True iff @a x is lexicographically less than @a y. |
| * |
| * This is a total ordering relation. It is linear in the size of the |
| * maps. The elements must be comparable with @c <. |
| * |
| * See std::lexicographical_compare() for how the determination is made. |
| */ |
| template <typename _Key, typename _Tp, typename _Compare, typename _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; } |
| |
| /// Based on operator== |
| template <typename _Key, typename _Tp, typename _Compare, typename _Alloc> |
| inline bool |
| operator!=(const map<_Key,_Tp,_Compare,_Alloc>& __x, |
| const map<_Key,_Tp,_Compare,_Alloc>& __y) |
| { return !(__x == __y); } |
| |
| /// Based on operator< |
| template <typename _Key, typename _Tp, typename _Compare, typename _Alloc> |
| inline bool |
| operator>(const map<_Key,_Tp,_Compare,_Alloc>& __x, |
| const map<_Key,_Tp,_Compare,_Alloc>& __y) |
| { return __y < __x; } |
| |
| /// Based on operator< |
| template <typename _Key, typename _Tp, typename _Compare, typename _Alloc> |
| inline bool |
| operator<=(const map<_Key,_Tp,_Compare,_Alloc>& __x, |
| const map<_Key,_Tp,_Compare,_Alloc>& __y) |
| { return !(__y < __x); } |
| |
| /// Based on operator< |
| template <typename _Key, typename _Tp, typename _Compare, typename _Alloc> |
| inline bool |
| operator>=(const map<_Key,_Tp,_Compare,_Alloc>& __x, |
| const map<_Key,_Tp,_Compare,_Alloc>& __y) |
| { return !(__x < __y); } |
| |
| /// See std::map::swap(). |
| template <typename _Key, typename _Tp, typename _Compare, typename _Alloc> |
| inline void |
| swap(map<_Key,_Tp,_Compare,_Alloc>& __x, map<_Key,_Tp,_Compare,_Alloc>& __y) |
| { __x.swap(__y); } |
| } // namespace std |
| |
| #endif /* _MAP_H */ |
