template <class _T1, class _T2>
inline void _Construct(_T1* __p, const _T2& __value) {
  new ((void*) __p) _T1(__value);                placement new运算符：在已分配的内存上构造函数对象。opreator new ，new opreator，placement new区别请<a target=_blank href="http://www.cnblogs.com/luxiaoxun/archive/2012/08/10/2631812.html">Google</a>
}

template <class _T1>
inline void _Construct(_T1* __p) {
  new ((void*) __p) _T1();
}

template <class _Tp>
inline void _Destroy(_Tp* __pointer) {
  __pointer->~_Tp();
}

template <class _ForwardIterator>
void
__destroy_aux(_ForwardIterator __first, _ForwardIterator __last, __false_type)
{
  for ( ; __first != __last; ++__first)
    destroy(&*__first);
}

template <class _ForwardIterator> 
inline void __destroy_aux(_ForwardIterator, _ForwardIterator, __true_type) {}

template <class _ForwardIterator, class _Tp>
inline void 
__destroy(_ForwardIterator __first, _ForwardIterator __last, _Tp*)
{
  typedef typename __type_traits<_Tp>::has_trivial_destructor
          _Trivial_destructor;
  __destroy_aux(__first, __last, _Trivial_destructor());
}

template <class _ForwardIterator>
inline void _Destroy(_ForwardIterator __first, _ForwardIterator __last) {
  __destroy(__first, __last, __VALUE_TYPE(__first));
}

inline void _Destroy(char*, char*) {}
inline void _Destroy(int*, int*) {}
inline void _Destroy(long*, long*) {}
inline void _Destroy(float*, float*) {}
inline void _Destroy(double*, double*) {}
#ifdef __STL_HAS_WCHAR_T
inline void _Destroy(wchar_t*, wchar_t*) {}

文件：stl_uninitialized.h

分析众多函数中的一个：uninitialized_copy   函数。
这个函数一共有三个版本：一个模板函数，一个char类型重载，一个wchar类型重载。具体请看。
char类型重载：
inline char* uninitialized_copy(const char* __first, const char* __last,char* __result) {
  memmove(__result, __first, __last - __first);
  return __result + (__last - __first);
}

wchar类型重载：
inline wchar_t* uninitialized_copy(const wchar_t* __first, const wchar_t* __last,wchar_t* __result)
{
  memmove(__result, __first, sizeof(wchar_t) * (__last - __first));
  return __result + (__last - __first);
}

模板类型：用到了类型特性萃取
template <class _InputIter, class _ForwardIter>
inline _ForwardIter
  uninitialized_copy(_InputIter __first, _InputIter __last, _ForwardIter __result)
{
  return __uninitialized_copy(__first, __last, __result,__VALUE_TYPE(__result));
}

template <class _InputIter, class _ForwardIter, class _Tp>
inline _ForwardIter
__uninitialized_copy(_InputIter __first, _InputIter __last,_ForwardIter __result, _Tp*)
{
  typedef typename __type_traits<_Tp>::is_POD_type _Is_POD;
  return __uninitialized_copy_aux(__first, __last, __result, _Is_POD());
}

template <class _InputIter, class _ForwardIter>
inline _ForwardIter 
__uninitialized_copy_aux(_InputIter __first, _InputIter __last,_ForwardIter __result,__true_type)
{
  return copy(__first, __last, __result);
}

template <class _InputIter, class _ForwardIter>
_ForwardIter 
__uninitialized_copy_aux(_InputIter __first, _InputIter __last,
                         _ForwardIter __result,
                         __false_type)
{
  _ForwardIter __cur = __result;
  __STL_TRY {
    for ( ; __first != __last; ++__first, ++__cur)
      _Construct(&*__cur, *__first);
    return __cur;
  }
  __STL_UNWIND(_Destroy(__result, __cur));
}

一二级内存分配器（使用malloc）

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