SGI源码注释之stl_vector.h初窥

<textarea cols="50" rows="15" name="code" class="cpp">template &lt;class _Tp, class _Allocator, bool _IsStatic&gt; class _Vector_alloc_base { public: typedef typename _Alloc_traits&lt;_Tp, _Allocator&gt;::allocator_type allocator_type; allocator_type get_allocator() const { return _M_data_allocator; } _Vector_alloc_base(const allocator_type&amp; __a) : _M_data_allocator(__a), _M_start(0), _M_finish(0), _M_end_of_storage(0) {} //构造函数,将开始位置,尾部位置,可用存储位置 置零 protected: allocator_type _M_data_allocator; _Tp* _M_start;//开始位置 _Tp* _M_finish;//可用存储位置 _Tp* _M_end_of_storage;//可用空间尾部位置 _Tp* _M_allocate(size_t __n) { return _M_data_allocator.allocate(__n); } //分配内存 void _M_deallocate(_Tp* __p, size_t __n) { if (__p) _M_data_allocator.deallocate(__p, __n); } //回收内存 }; // Specialization for allocators that have the property that we don't // actually have to store an allocator object. template &lt;class _Tp, class _Allocator&gt; //重载没有bool _IsStatic的_Vector_alloc_base class _Vector_alloc_base&lt;_Tp, _Allocator, true&gt; { public: typedef typename _Alloc_traits&lt;_Tp, _Allocator&gt;::allocator_type allocator_type; allocator_type get_allocator() const { return allocator_type(); } _Vector_alloc_base(const allocator_type&amp;) : _M_start(0), _M_finish(0), _M_end_of_storage(0) {} protected: _Tp* _M_start; _Tp* _M_finish; _Tp* _M_end_of_storage; typedef typename _Alloc_traits&lt;_Tp, _Allocator&gt;::_Alloc_type _Alloc_type; _Tp* _M_allocate(size_t __n) { return _Alloc_type::allocate(__n); } void _M_deallocate(_Tp* __p, size_t __n) { _Alloc_type::deallocate(__p, __n);} }; template &lt;class _Tp, class _Alloc&gt; struct _Vector_base : public _Vector_alloc_base&lt;_Tp, _Alloc, _Alloc_traits&lt;_Tp, _Alloc&gt;::_S_instanceless&gt; //_Vector_base继承自_Vector_alloc_base,由于此处的结构为其接口，设置为private没有什么意义 //由此可见作者的务实 { typedef _Vector_alloc_base&lt;_Tp, _Alloc, _Alloc_traits&lt;_Tp, _Alloc&gt;::_S_instanceless&gt; _Base; typedef typename _Base::allocator_type allocator_type; _Vector_base(const allocator_type&amp; __a) : _Base(__a) {} //_Vector_base构造函数 _Vector_base(size_t __n, const allocator_type&amp; __a) : _Base(__a) { _M_start = _M_allocate(__n); _M_finish = _M_start; _M_end_of_storage = _M_start + __n; } ~_Vector_base() { _M_deallocate(_M_start, _M_end_of_storage - _M_start); }//释放_Vector_base,回收空间 }; #else /* __STL_USE_STD_ALLOCATORS */ //使用标准的空间分配工具 template &lt;class _Tp, class _Alloc&gt; class _Vector_base { public: typedef _Alloc allocator_type; allocator_type get_allocator() const { return allocator_type(); } _Vector_base(const _Alloc&amp;) : _M_start(0), _M_finish(0), _M_end_of_storage(0) {} _Vector_base(size_t __n, const _Alloc&amp;) : _M_start(0), _M_finish(0), _M_end_of_storage(0) { _M_start = _M_allocate(__n); _M_finish = _M_start; _M_end_of_storage = _M_start + __n; } ~_Vector_base() { _M_deallocate(_M_start, _M_end_of_storage - _M_start); } protected: _Tp* _M_start;//开始位置 _Tp* _M_finish;//目前尾部位置 _Tp* _M_end_of_storage; //可用空间尾部位置 typedef simple_alloc&lt;_Tp, _Alloc&gt; _M_data_allocator;//此处使用的是simple_alloc _Tp* _M_allocate(size_t __n) { return _M_data_allocator::allocate(__n); } void _M_deallocate(_Tp* __p, size_t __n) { _M_data_allocator::deallocate(__p, __n); } }; #endif /* __STL_USE_STD_ALLOCATORS */ template &lt;class _Tp, class _Alloc = __STL_DEFAULT_ALLOCATOR(_Tp) &gt; class vector : protected _Vector_base&lt;_Tp, _Alloc&gt; { // requirements: __STL_CLASS_REQUIRES(_Tp, _Assignable); private: typedef _Vector_base&lt;_Tp, _Alloc&gt; _Base; public: typedef _Tp value_type; typedef value_type* pointer; typedef const value_type* const_pointer; typedef value_type* iterator; typedef const value_type* const_iterator; typedef value_type&amp; reference; typedef const value_type&amp; const_reference; typedef size_t size_type; typedef ptrdiff_t difference_type; //Trait技巧 typedef typename _Base::allocator_type allocator_type; allocator_type get_allocator() const { return _Base::get_allocator(); } #ifdef __STL_CLASS_PARTIAL_SPECIALIZATION typedef reverse_iterator&lt;const_iterator&gt; const_reverse_iterator; typedef reverse_iterator&lt;iterator&gt; reverse_iterator; #else /* __STL_CLASS_PARTIAL_SPECIALIZATION */ typedef reverse_iterator&lt;const_iterator, value_type, const_reference, difference_type&gt; const_reverse_iterator; typedef reverse_iterator&lt;iterator, value_type, reference, difference_type&gt; reverse_iterator; #endif /* __STL_CLASS_PARTIAL_SPECIALIZATION */ protected: #ifdef __STL_HAS_NAMESPACES using _Base::_M_allocate; using _Base::_M_deallocate; using _Base::_M_start; using _Base::_M_finish; using _Base::_M_end_of_storage; #endif /* __STL_HAS_NAMESPACES */ protected: void _M_insert_aux(iterator __position, const _Tp&amp; __x); void _M_insert_aux(iterator __position); public: iterator begin() { return _M_start; }//返回第一个元素的迭代器 const_iterator begin() const { return _M_start; } iterator end() { return _M_finish; }//返回最末元素的迭代器(实指向最末元素的下一个位置) const_iterator end() const { return _M_finish; } reverse_iterator rbegin()//返回Vector尾部的逆迭代器 { return reverse_iterator(end()); } const_reverse_iterator rbegin() const { return const_reverse_iterator(end()); } reverse_iterator rend()//返回Vector起始的逆迭代器 { return reverse_iterator(begin()); } const_reverse_iterator rend() const { return const_reverse_iterator(begin()); } size_type size() const//返回Vector元素数量的大小 { return size_type(end() - begin()); } size_type max_size() const//返回Vector所能容纳元素的最大数量（上限） { return size_type(-1) / sizeof(_Tp); } size_type capacity() const//返回vector所能容纳的元素数量(在不重新分配内存的情况下） { return size_type(_M_end_of_storage - begin()); } bool empty() const//判断Vector是否为空（返回true时为空） { return begin() == end(); } reference operator[](size_type __n) { return *(begin() + __n); }//重载[]的引用 const_reference operator[](size_type __n) const { return *(begin() + __n); } #ifdef __STL_THROW_RANGE_ERRORS void _M_range_check(size_type __n) const { if (__n &gt;= this-&gt;size()) __stl_throw_range_error("vector"); } reference at(size_type __n) { _M_range_check(__n); return (*this)[__n]; } const_reference at(size_type __n) const { _M_range_check(__n); return (*this)[__n]; } #endif /* __STL_THROW_RANGE_ERRORS */ ///////////////////////////Vector的多个构造函数////////////////////////////////////// explicit vector(const allocator_type&amp; __a = allocator_type()) : _Base(__a) {} //指定vector初始大小__n,与初值__value vector(size_type __n, const _Tp&amp; __value, const allocator_type&amp; __a = allocator_type()) : _Base(__n, __a) { _M_finish = uninitialized_fill_n(_M_start, __n, __value); } explicit vector(size_type __n) : _Base(__n, allocator_type()) { _M_finish = uninitialized_fill_n(_M_start, __n, _Tp()); } vector(const vector&lt;_Tp, _Alloc&gt;&amp; __x) : _Base(__x.size(), __x.get_allocator()) { _M_finish = uninitialized_copy(__x.begin(), __x.end(), _M_start); } #ifdef __STL_MEMBER_TEMPLATES // Check whether it's an integral type. If so, it's not an iterator. template &lt;class _InputIterator&gt; vector(_InputIterator __first, _InputIterator __last, const allocator_type&amp; __a = allocator_type()) : _Base(__a) { typedef typename _Is_integer&lt;_InputIterator&gt;::_Integral _Integral; _M_initialize_aux(__first, __last, _Integral()); } template &lt;class _Integer&gt; void _M_initialize_aux(_Integer __n, _Integer __value, __true_type) { _M_start = _M_allocate(__n); _M_end_of_storage = _M_start + __n; _M_finish = uninitialized_fill_n(_M_start, __n, __value); } template &lt;class _InputIterator&gt; void _M_initialize_aux(_InputIterator __first, _InputIterator __last, __false_type) { _M_range_initialize(__first, __last, __ITERATOR_CATEGORY(__first)); } #else vector(const _Tp* __first, const _Tp* __last, const allocator_type&amp; __a = allocator_type()) : _Base(__last - __first, __a) { _M_finish = uninitialized_copy(__first, __last, _M_start); } #endif /* __STL_MEMBER_TEMPLATES */ //////////////////////////////////////////////////////////////////////////////////// ~vector() { destroy(_M_start, _M_finish); }//销毁资源,destroy为全局函数 vector&lt;_Tp, _Alloc&gt;&amp; operator=(const vector&lt;_Tp, _Alloc&gt;&amp; __x); void reserve(size_type __n) { if (capacity() &lt; __n) { const size_type __old_size = size(); iterator __tmp = _M_allocate_and_copy(__n, _M_start, _M_finish); destroy(_M_start, _M_finish); _M_deallocate(_M_start, _M_end_of_storage - _M_start); _M_start = __tmp; _M_finish = __tmp + __old_size; _M_end_of_storage = _M_start + __n; } } // assign(), a generalized assignment member function. Two // versions: one that takes a count, and one that takes a range. // The range version is a member template, so we dispatch on whether // or not the type is an integer. //此处的赋值函数assign()存在两个版本,第一个版本把__n个值为_val的元素赋到vector中 //第二个版本将区间[__first，__last)的元素赋到当前vector中。 //区间赋值的版本是一个成员模板 void assign(size_type __n, const _Tp&amp; __val) { _M_fill_assign(__n, __val); } void _M_fill_assign(size_type __n, const _Tp&amp; __val); #ifdef __STL_MEMBER_TEMPLATES template &lt;class _InputIterator&gt; void assign(_InputIterator __first, _InputIterator __last) { typedef typename _Is_integer&lt;_InputIterator&gt;::_Integral _Integral; _M_assign_dispatch(__first, __last, _Integral()); } template &lt;class _Integer&gt; void _M_assign_dispatch(_Integer __n, _Integer __val, __true_type) { _M_fill_assign((size_type) __n, (_Tp) __val); } template &lt;class _InputIter&gt; void _M_assign_dispatch(_InputIter __first, _InputIter __last, __false_type) { _M_assign_aux(__first, __last, __ITERATOR_CATEGORY(__first)); } template &lt;class _InputIterator&gt; void _M_assign_aux(_InputIterator __first, _InputIterator __last, input_iterator_tag); template &lt;class _ForwardIterator&gt; void _M_assign_aux(_ForwardIterator __first, _ForwardIterator __last, forward_iterator_tag); #endif /* __STL_MEMBER_TEMPLATES */ reference front() { return *begin(); }//返回第一个元素 const_reference front() const { return *begin(); } reference back() { return *(end() - 1); }//返回最末一个元素 const_reference back() const { return *(end() - 1); } void push_back(const _Tp&amp; __x) {//传说中的push_back函数,添加值为__x的元素到当前vector末尾 if (_M_finish != _M_end_of_storage) {//空间还没用完的情形 construct(_M_finish, __x); ++_M_finish; } else _M_insert_aux(end(), __x); } void push_back() { if (_M_finish != _M_end_of_storage) { construct(_M_finish); ++_M_finish; } else _M_insert_aux(end()); } void swap(vector&lt;_Tp, _Alloc&gt;&amp; __x) {//交换两个Vector __STD::swap(_M_start, __x._M_start); __STD::swap(_M_finish, __x._M_finish); __STD::swap(_M_end_of_storage, __x._M_end_of_storage); } iterator insert(iterator __position, const _Tp&amp; __x) {//在指定位置__position前插入值为__x的元素 //返回指向这个元素的迭代器, size_type __n = __position - begin(); if (_M_finish != _M_end_of_storage &amp;&amp; __position == end()) { construct(_M_finish, __x); ++_M_finish; } else _M_insert_aux(__position, __x); return begin() + __n; } iterator insert(iterator __position) { size_type __n = __position - begin(); if (_M_finish != _M_end_of_storage &amp;&amp; __position == end()) { construct(_M_finish); ++_M_finish; } else _M_insert_aux(__position); return begin() + __n; } #ifdef __STL_MEMBER_TEMPLATES // Check whether it's an integral type. If so, it's not an iterator. template &lt;class _InputIterator&gt; void insert(iterator __pos, _InputIterator __first, _InputIterator __last) {//在指定位置__pos前插入区间[__first,__last)的所有元素 typedef typename _Is_integer&lt;_InputIterator&gt;::_Integral _Integral; _M_insert_dispatch(__pos, __first, __last, _Integral()); } template &lt;class _Integer&gt; void _M_insert_dispatch(iterator __pos, _Integer __n, _Integer __val, __true_type) { _M_fill_insert(__pos, (size_type) __n, (_Tp) __val); } template &lt;class _InputIterator&gt; void _M_insert_dispatch(iterator __pos, _InputIterator __first, _InputIterator __last, __false_type) { _M_range_insert(__pos, __first, __last, __ITERATOR_CATEGORY(__first)); } #else /* __STL_MEMBER_TEMPLATES */ void insert(iterator __position, const_iterator __first, const_iterator __last); #endif /* __STL_MEMBER_TEMPLATES */ void insert (iterator __pos, size_type __n, const _Tp&amp; __x)//在指定位置__pos前插入__n,个值为__x的元素 { _M_fill_insert(__pos, __n, __x); } void _M_fill_insert (iterator __pos, size_type __n, const _Tp&amp; __x); void pop_back() {//移除最后一个元素 --_M_finish; destroy(_M_finish); } iterator erase(iterator __position) {//erase函数删除指定位置__position的元素 if (__position + 1 != end()) copy(__position + 1, _M_finish, __position); --_M_finish; destroy(_M_finish); return __position; } iterator erase(iterator __first, iterator __last) {//删除区间[__first, __last)的所有元素 iterator __i = copy(__last, _M_finish, __first); destroy(__i, _M_finish); _M_finish = _M_finish - (__last - __first); return __first; } void resize(size_type __new_size, const _Tp&amp; __x) {//改变当前vector的大小为__new_size且对新创建的元素赋值__x if (__new_size &lt; size()) erase(begin() + __new_size, end()); else insert(end(), __new_size - size(), __x); } void resize(size_type __new_size) { resize(__new_size, _Tp()); }//为当前vector预留至少共容纳size个元素的空间 void clear() { erase(begin(), end()); }//清空所有元素 protected: #ifdef __STL_MEMBER_TEMPLATES template &lt;class _ForwardIterator&gt; iterator _M_allocate_and_copy(size_type __n, _ForwardIterator __first, _ForwardIterator __last) { iterator __result = _M_allocate(__n); __STL_TRY { uninitialized_copy(__first, __last, __result); return __result; } __STL_UNWIND(_M_deallocate(__result, __n)); } #else /* __STL_MEMBER_TEMPLATES */ iterator _M_allocate_and_copy(size_type __n, const_iterator __first, const_iterator __last) { iterator __result = _M_allocate(__n); __STL_TRY { uninitialized_copy(__first, __last, __result); return __result; } __STL_UNWIND(_M_deallocate(__result, __n)); } #endif /* __STL_MEMBER_TEMPLATES */ #ifdef __STL_MEMBER_TEMPLATES template &lt;class _InputIterator&gt; void _M_range_initialize(_InputIterator __first, _InputIterator __last, input_iterator_tag) { for ( ; __first != __last; ++__first) push_back(*__first); } // This function is only called by the constructor. 该函数只在构造函数时调用 template &lt;class _ForwardIterator&gt; void _M_range_initialize(_ForwardIterator __first, _ForwardIterator __last, forward_iterator_tag) { size_type __n = 0; distance(__first, __last, __n); _M_start = _M_allocate(__n); _M_end_of_storage = _M_start + __n; _M_finish = uninitialized_copy(__first, __last, _M_start); } template &lt;class _InputIterator&gt; void _M_range_insert(iterator __pos, _InputIterator __first, _InputIterator __last, input_iterator_tag); template &lt;class _ForwardIterator&gt; void _M_range_insert(iterator __pos, _ForwardIterator __first, _ForwardIterator __last, forward_iterator_tag); #endif /* __STL_MEMBER_TEMPLATES */ }; template &lt;class _Tp, class _Alloc&gt; inline bool operator==(const vector&lt;_Tp, _Alloc&gt;&amp; __x, const vector&lt;_Tp, _Alloc&gt;&amp; __y) { return __x.size() == __y.size() &amp;&amp; equal(__x.begin(), __x.end(), __y.begin()); } template &lt;class _Tp, class _Alloc&gt; inline bool operator&lt;(const vector&lt;_Tp, _Alloc&gt;&amp; __x, const vector&lt;_Tp, _Alloc&gt;&amp; __y) { return lexicographical_compare(__x.begin(), __x.end(), __y.begin(), __y.end()); } #ifdef __STL_FUNCTION_TMPL_PARTIAL_ORDER template &lt;class _Tp, class _Alloc&gt; inline void swap(vector&lt;_Tp, _Alloc&gt;&amp; __x, vector&lt;_Tp, _Alloc&gt;&amp; __y) { __x.swap(__y); } template &lt;class _Tp, class _Alloc&gt; inline bool operator!=(const vector&lt;_Tp, _Alloc&gt;&amp; __x, const vector&lt;_Tp, _Alloc&gt;&amp; __y) { return !(__x == __y); } template &lt;class _Tp, class _Alloc&gt; inline bool operator&gt;(const vector&lt;_Tp, _Alloc&gt;&amp; __x, const vector&lt;_Tp, _Alloc&gt;&amp; __y) { return __y &lt; __x; } template &lt;class _Tp, class _Alloc&gt; inline bool operator&lt;=(const vector&lt;_Tp, _Alloc&gt;&amp; __x, const vector&lt;_Tp, _Alloc&gt;&amp; __y) { return !(__y &lt; __x); } template &lt;class _Tp, class _Alloc&gt; inline bool operator&gt;=(const vector&lt;_Tp, _Alloc&gt;&amp; __x, const vector&lt;_Tp, _Alloc&gt;&amp; __y) { return !(__x &lt; __y); } #endif /* __STL_FUNCTION_TMPL_PARTIAL_ORDER */ template &lt;class _Tp, class _Alloc&gt; vector&lt;_Tp,_Alloc&gt;&amp; vector&lt;_Tp,_Alloc&gt;::operator=(const vector&lt;_Tp, _Alloc&gt;&amp; __x)//重载&ldquo;=&rdquo;运算符 { if (&amp;__x != this) {//此处考虑了自赋值的问题，参考EffectiveC++ 3th Item11 const size_type __xlen = __x.size(); if (__xlen &gt; capacity()) {//被赋值对象所能容纳的元素数量不够 iterator __tmp = _M_allocate_and_copy(__xlen, __x.begin(), __x.end());//重新分配空间 destroy(_M_start, _M_finish); _M_deallocate(_M_start, _M_end_of_storage - _M_start); _M_start = __tmp; _M_end_of_storage = _M_start + __xlen; } else if (size() &gt;= __xlen) {//被赋值对象的数量足够大.直接复制 iterator __i = copy(__x.begin(), __x.end(), begin()); destroy(__i, _M_finish); } else { copy(__x.begin(), __x.begin() + size(), _M_start); uninitialized_copy(__x.begin() + size(), __x.end(), _M_finish); } _M_finish = _M_start + __xlen; } return *this; } template &lt;class _Tp, class _Alloc&gt; void vector&lt;_Tp, _Alloc&gt;::_M_fill_assign(size_t __n, const value_type&amp; __val) { if (__n &gt; capacity()) { vector&lt;_Tp, _Alloc&gt; __tmp(__n, __val, get_allocator()); __tmp.swap(*this); } else if (__n &gt; size()) { fill(begin(), end(), __val); _M_finish = uninitialized_fill_n(_M_finish, __n - size(), __val); } else erase(fill_n(begin(), __n, __val), end()); } #ifdef __STL_MEMBER_TEMPLATES template &lt;class _Tp, class _Alloc&gt; template &lt;class _InputIter&gt; void vector&lt;_Tp, _Alloc&gt;::_M_assign_aux(_InputIter __first, _InputIter __last, input_iterator_tag) { iterator __cur = begin(); for ( ; __first != __last &amp;&amp; __cur != end(); ++__cur, ++__first) *__cur = *__first; if (__first == __last) erase(__cur, end()); else insert(end(), __first, __last); } template &lt;class _Tp, class _Alloc&gt; template &lt;class _ForwardIter&gt; void vector&lt;_Tp, _Alloc&gt;::_M_assign_aux(_ForwardIter __first, _ForwardIter __last, forward_iterator_tag) { size_type __len = 0; distance(__first, __last, __len); if (__len &gt; capacity()) { iterator __tmp = _M_allocate_and_copy(__len, __first, __last); destroy(_M_start, _M_finish); _M_deallocate(_M_start, _M_end_of_storage - _M_start); _M_start = __tmp; _M_end_of_storage = _M_finish = _M_start + __len; } else if (size() &gt;= __len) { iterator __new_finish = copy(__first, __last, _M_start); destroy(__new_finish, _M_finish); _M_finish = __new_finish; } else { _ForwardIter __mid = __first; advance(__mid, size()); copy(__first, __mid, _M_start); _M_finish = uninitialized_copy(__mid, __last, _M_finish); } } #endif /* __STL_MEMBER_TEMPLATES */ template &lt;class _Tp, class _Alloc&gt; void vector&lt;_Tp, _Alloc&gt;::_M_insert_aux(iterator __position, const _Tp&amp; __x) { if (_M_finish != _M_end_of_storage) { construct(_M_finish, *(_M_finish - 1)); ++_M_finish; _Tp __x_copy = __x; copy_backward(__position, _M_finish - 2, _M_finish - 1); *__position = __x_copy; } else { const size_type __old_size = size(); const size_type __len = __old_size != 0 ? 2 * __old_size : 1; iterator __new_start = _M_allocate(__len); iterator __new_finish = __new_start; __STL_TRY { __new_finish = uninitialized_copy(_M_start, __position, __new_start); construct(__new_finish, __x); ++__new_finish; __new_finish = uninitialized_copy(__position, _M_finish, __new_finish); } __STL_UNWIND((destroy(__new_start,__new_finish), _M_deallocate(__new_start,__len))); destroy(begin(), end()); _M_deallocate(_M_start, _M_end_of_storage - _M_start); _M_start = __new_start; _M_finish = __new_finish; _M_end_of_storage = __new_start + __len; } } template &lt;class _Tp, class _Alloc&gt; void vector&lt;_Tp, _Alloc&gt;::_M_insert_aux(iterator __position) { if (_M_finish != _M_end_of_storage) { construct(_M_finish, *(_M_finish - 1)); ++_M_finish; copy_backward(__position, _M_finish - 2, _M_finish - 1); *__position = _Tp(); } else { const size_type __old_size = size(); const size_type __len = __old_size != 0 ? 2 * __old_size : 1; iterator __new_start = _M_allocate(__len); iterator __new_finish = __new_start; __STL_TRY { __new_finish = uninitialized_copy(_M_start, __position, __new_start); construct(__new_finish); ++__new_finish; __new_finish = uninitialized_copy(__position, _M_finish, __new_finish); } __STL_UNWIND((destroy(__new_start,__new_finish), _M_deallocate(__new_start,__len))); destroy(begin(), end()); _M_deallocate(_M_start, _M_end_of_storage - _M_start); _M_start = __new_start; _M_finish = __new_finish; _M_end_of_storage = __new_start + __len; } } template &lt;class _Tp, class _Alloc&gt; void vector&lt;_Tp, _Alloc&gt;::_M_fill_insert(iterator __position, size_type __n, const _Tp&amp; __x) { if (__n != 0) { if (size_type(_M_end_of_storage - _M_finish) &gt;= __n) { _Tp __x_copy = __x; const size_type __elems_after = _M_finish - __position; iterator __old_finish = _M_finish; if (__elems_after &gt; __n) { uninitialized_copy(_M_finish - __n, _M_finish, _M_finish); _M_finish += __n; copy_backward(__position, __old_finish - __n, __old_finish); fill(__position, __position + __n, __x_copy); } else { uninitialized_fill_n(_M_finish, __n - __elems_after, __x_copy); _M_finish += __n - __elems_after; uninitialized_copy(__position, __old_finish, _M_finish); _M_finish += __elems_after; fill(__position, __old_finish, __x_copy); } } else { const size_type __old_size = size(); const size_type __len = __old_size + max(__old_size, __n); iterator __new_start = _M_allocate(__len); iterator __new_finish = __new_start; __STL_TRY { __new_finish = uninitialized_copy(_M_start, __position, __new_start); __new_finish = uninitialized_fill_n(__new_finish, __n, __x); __new_finish = uninitialized_copy(__position, _M_finish, __new_finish); } __STL_UNWIND((destroy(__new_start,__new_finish), _M_deallocate(__new_start,__len))); destroy(_M_start, _M_finish); _M_deallocate(_M_start, _M_end_of_storage - _M_start); _M_start = __new_start; _M_finish = __new_finish; _M_end_of_storage = __new_start + __len; } } } #ifdef __STL_MEMBER_TEMPLATES template &lt;class _Tp, class _Alloc&gt; template &lt;class _InputIterator&gt; void vector&lt;_Tp, _Alloc&gt;::_M_range_insert(iterator __pos, _InputIterator __first, _InputIterator __last, input_iterator_tag) { for ( ; __first != __last; ++__first) { __pos = insert(__pos, *__first); ++__pos; } } template &lt;class _Tp, class _Alloc&gt; template &lt;class _ForwardIterator&gt; void vector&lt;_Tp, _Alloc&gt;::_M_range_insert(iterator __position, _ForwardIterator __first, _ForwardIterator __last, forward_iterator_tag) { if (__first != __last) { size_type __n = 0; distance(__first, __last, __n); if (size_type(_M_end_of_storage - _M_finish) &gt;= __n) { const size_type __elems_after = _M_finish - __position; iterator __old_finish = _M_finish; if (__elems_after &gt; __n) { uninitialized_copy(_M_finish - __n, _M_finish, _M_finish); _M_finish += __n; copy_backward(__position, __old_finish - __n, __old_finish); copy(__first, __last, __position); } else { _ForwardIterator __mid = __first; advance(__mid, __elems_after); uninitialized_copy(__mid, __last, _M_finish); _M_finish += __n - __elems_after; uninitialized_copy(__position, __old_finish, _M_finish); _M_finish += __elems_after; copy(__first, __mid, __position); } } else { const size_type __old_size = size(); const size_type __len = __old_size + max(__old_size, __n); iterator __new_start = _M_allocate(__len); iterator __new_finish = __new_start; __STL_TRY { __new_finish = uninitialized_copy(_M_start, __position, __new_start); __new_finish = uninitialized_copy(__first, __last, __new_finish); __new_finish = uninitialized_copy(__position, _M_finish, __new_finish); } __STL_UNWIND((destroy(__new_start,__new_finish), _M_deallocate(__new_start,__len))); destroy(_M_start, _M_finish); _M_deallocate(_M_start, _M_end_of_storage - _M_start); _M_start = __new_start; _M_finish = __new_finish; _M_end_of_storage = __new_start + __len; } } } #else /* __STL_MEMBER_TEMPLATES */ template &lt;class _Tp, class _Alloc&gt; void vector&lt;_Tp, _Alloc&gt;::insert(iterator __position, const_iterator __first, const_iterator __last) { if (__first != __last) { size_type __n = 0; distance(__first, __last, __n); if (size_type(_M_end_of_storage - _M_finish) &gt;= __n) { const size_type __elems_after = _M_finish - __position; iterator __old_finish = _M_finish; if (__elems_after &gt; __n) { uninitialized_copy(_M_finish - __n, _M_finish, _M_finish); _M_finish += __n; copy_backward(__position, __old_finish - __n, __old_finish); copy(__first, __last, __position); } else { uninitialized_copy(__first + __elems_after, __last, _M_finish); _M_finish += __n - __elems_after; uninitialized_copy(__position, __old_finish, _M_finish); _M_finish += __elems_after; copy(__first, __first + __elems_after, __position); } } else { const size_type __old_size = size(); const size_type __len = __old_size + max(__old_size, __n); iterator __new_start = _M_allocate(__len); iterator __new_finish = __new_start; __STL_TRY { __new_finish = uninitialized_copy(_M_start, __position, __new_start); __new_finish = uninitialized_copy(__first, __last, __new_finish); __new_finish = uninitialized_copy(__position, _M_finish, __new_finish); } __STL_UNWIND((destroy(__new_start,__new_finish), _M_deallocate(__new_start,__len))); destroy(_M_start, _M_finish); _M_deallocate(_M_start, _M_end_of_storage - _M_start); _M_start = __new_start; _M_finish = __new_finish; _M_end_of_storage = __new_start + __len; } } } #endif /* __STL_MEMBER_TEMPLATES */ #if defined(__sgi) &amp;&amp; !defined(__GNUC__) &amp;&amp; (_MIPS_SIM != _MIPS_SIM_ABI32) #pragma reset woff 1174 #pragma reset woff 1375 #endif __STL_END_NAMESPACE #endif /* __SGI_STL_INTERNAL_VECTOR_H */ // Local Variables: // mode:C++ // End: </textarea>