STL source code analysis --- stl_map.h Reading Notes

Map is a standard relational container in STL. It stores pair elements with key-value keys and real-value values. Store the data in the red/black tree according to the key value. Two elements with the same key value are not allowed in map. When an element is inserted into the red/black tree, the key-value key cannot be modified, but the value can be modified because the map iterator is not a constant iterator, but a mutable iterator.

G ++ 2.91.57, Cygnus \ cygwin-b20 \ include \ G ++ \ stl_map.h complete list/*** copyright (c) 1994 * Hewlett-Packard Company ** permission to use, copy, modify, distribute and modify this software * and its documentation for any purpose is hereby granted without handle, * 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 merge this software * and its documentation for any purpose is hereby granted without tables ,* 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. * // * Note: This is an internal header file, encoded ded by other STL Header S. * You shoshould not attempt to use it directly. */# ifndef _ sgi_stl_internal_map_h # DEFINE _ alias # If defined (_ SGI )&&! Defined (_ gnuc _) & (_ mips_sim! = _ Mips_sim_abi32) # pragma set woff 1174 # endif # ifndef _ stl_limited_default_templates // key is the key-value type, and T is the real-value data type template <class key, class t, class compare = less <key>, class alloc = alloc> # elsetemplate <class key, class T, class compare, class alloc = alloc> # endifclass map {public: // typedefs: typedef key key_type; // key value type typedef t data_type; // real value, data type typedef t mapped_type; // typedef pair <const key, T> value_type; // element type (key value/true value) typedef compare key_compare; // A comparison function of key value // The following defines a functo, which calls the element comparison function. Class value_compare: Public binary_function <value_type, value_type, bool> {friend class Map <key, T, compare, alloc>; protected: Compare comp; value_compare (compare C ): comp (c) {} public: // overload () is the element comparison function bool operator () (const value_type & X, const value_type & Y) const {return comp (X. first, Y. first) ;}}; PRIVATE: // use the first type of Map (A Pair) as the key value type of the TB-tree. // Therefore, in the Rb-tree, the key-value key cannot be modified, but the value data can be modified. Typedef rb_tree <key_type, value_type, select1st <value_type>, key_compare, alloc> rep_type; rep_type t; // The Red/black tree acts as the underlying data structure public: typedef typename rep_type: pointer; typedef typename rep_type: const_pointer; typedef typename rep_type: Reference reference; typedef typename rep_type: const_reference; // const_iterator not defined as Rb-tree. I think the key value key cannot be modified, // but the value data can be modified. Typedef typename rep_type: iterator; typedef typename rep_type: Optional bytes; typedef typename rep_type: Required bytes; typedef typename rep_type: difference_type; // allocation/deallocation // note that map must use insert_un Ique () instead of insert_equal (). // Use insert_equal () only for multimap (). Map (): T (compare () {} explicit map (const compare & Comp): T (COMP) {}# ifdef _ stl_member_templates template <class inputiterator> map (inputiterator first, inputiterator last): T (compare () {T. insert_unique (first, last);} template <class inputiterator> map (inputiterator first, inputiterator last, const compare & Comp): T (COMP) {T. insert_unique (first, last) ;}# else map (const value_type * first, Const value_type * Last): T (compare () {T. insert_unique (first, last);} map (const value_type * First, const value_type * Last, const compare & Comp): T (COMP) {T. insert_unique (first, last);} map (const_iterator first, const_iterator last): T (compare () {T. insert_unique (first, last);} map (const_iterator first, const_iterator last, const compare & Comp): T (COMP) {T. insert_unique (first, last);} # E Ndif/* _ stl_member_templates */Map (const Map <key, T, compare, alloc> & X): T (X. t) {} Map <key, T, compare, alloc> & operator = (const Map <key, T, compare, alloc> & X) {T = x. t; return * This;} // accessors: // all the following map operation rows are provided by the RB-tree, so you only need to call the map operation. Key_compare key_comp () const {return T. key_comp ();} value_compare value_comp () const {return value_compare (T. key_comp ();} iterator begin () {return T. begin ();} const_iterator begin () const {return T. begin ();} iterator end () {return T. end ();} const_iterator end () const {return T. end ();} reverse_iterator rbegin () {return T. rbegin ();} const_reverse_iterator rbegin () const {return T. RBE Gin ();} reverse_iterator rend () {return T. rend ();} const_reverse_iterator rend () const {return T. rend ();} bool empty () const {return T. empty ();} size_type size () const {return T. size ();} size_type max_size () const {return T. max_size () ;}// reload []. The return value is T & operator [] (const key_type & K) {return (* (insert (value_type (K, T ()))). first )). second;} void swap (Map <key, T, compare, alloc> & X) {T. Swap (X. t);} // insert/Erase // note that the following insert statements return the pair <iterator, bool> insert (const value_type & X) {return T. insert_unique (x);} iterator insert (iterator position, const value_type & X) {return T. insert_unique (Position, x) ;}# ifdef _ stl_member_templates template <class inputiterator> void insert (inputiterator first, inputiterator last) {T. insert_unique (first, last);} # else void insert (const Value_type * First, const value_type * Last) {T. insert_unique (first, last);} void insert (const_iterator first, const_iterator last) {T. insert_unique (first, last);} # endif/* _ stl_member_templates */void erase (iterator position) {T. erase (position);} size_type erase (const key_type & X) {return T. erase (x);} void erase (iterator first, iterator last) {T. erase (first, last);} void clear () {T. cl Ear ();} // map operations: iterator find (const key_type & X) {return T. find (x);} const_iterator find (const key_type & X) const {return T. find (x);} size_type count (const key_type & X) const {return T. count (x);} iterator lower_bound (const key_type & X) {return T. lower_bound (x);} const_iterator lower_bound (const key_type & X) const {return T. lower_bound (x);} iterator upper_bound (const key_type & X) {return T. upper_bound (x);} const_iterator upper_bound (const key_type & X) const {return T. upper_bound (x);} pair <iterator, iterator> pai_range (const key_type & X) {return T. pai_range (x);} pair <const_iterator, const_iterator> pai_range (const key_type & X) const {return T. performance_range (x);} friend bool operator ==_ _ stl_null_tmpl_args (const map &, const map &); friend bool operator <_ stl_null _ Tmpl_args (const map &, const map &) ;}; template <class key, class T, class compare, class alloc> inline bool operator ==( const Map <key, t, compare, alloc> & X, const Map <key, T, compare, alloc> & Y) {return X. T = y. t;} template <class key, class T, class compare, class alloc> inline bool operator <(const Map <key, T, compare, alloc> & X, const Map <key, T, compare, alloc> & Y) {return X. T <Y. t ;}# ifdef _ s Tl_function_tmpl_partial_ordertemplate <class key, class T, class compare, class alloc> inline void swap (Map <key, T, compare, alloc> & X, Map <key, T, compare, alloc> & Y) {X. swap (y) ;}# endif/* _ stl_function_tmpl_partial_order */# If defined (_ SGI )&&! Defined (_ gnuc _) & (_ mips_sim! = _ Mips_sim_abi32) # pragma reset woff 1174 # endif _ stl_end_namespace # endif/* _ sgi_stl_internal_map_h * // local variables: // mode: C ++ // end: