云建站空间,wordpress 经典推荐,百度权重4,滁州市建设局网站近来看了看《STL源码剖析》中的空间配置器#xff0c;尝试着读了一下#xff0c;觉得模板还是强大的#xff0c;同时对于allocator的函数有了进一步的认识。
#if 0
#includememory
//alloctor 的必要接口
allocator::valuetype
allocator::pointer
allocator::cons… 近来看了看《STL源码剖析》中的空间配置器尝试着读了一下觉得模板还是强大的同时对于allocator的函数有了进一步的认识。
#if 0
#includememory
//alloctor 的必要接口
allocator::valuetype
allocator::pointer
allocator::const_pointer
allocator::reference
allocator::const_reference
allocator::size_type
allocator::difference_type
allocator::rebind
allocator::allocactor() //default constructor
allocator::allocator(const allocator) //copy constructor
template class Uallocator::allocator(const allocatorU) //泛化的 copy constructor
allocator::~allocator//default constructor
pointer allocator::address(reference x) const//返回某个对象的地址。a.address(x) const 等同于x
const_pointer allocator::address(const_reference x) const//返回某个const 对象的地址
pointer allocator::allocate(size_type n,const void* 0) //分配空间存n个对象。第二个参数是提示实现上可能会利用它来增进区域性可忽略
void allocator::deallocate(point p,size_type n) //归还当前分配的空间
size_type allocator::max_size() const //返回可成功分配的最大量
void allocator::construct(point p,const T x) //等同于new
void allocator::destroy(point p) //等同于p-~T()#endif//设计一个简单的空间配置器 allocator
//file:steem_alloc.h 自己的头文件
#ifndef _STEEMALLOC_
#define _STEEMALLOC_#includenew
#includecstddef
#includecstdlib
#includeclimits
#includeiostreamnamespace steem
{template class Tinline T* _allocate(ptrdiff_t size, T*){set_new_handler(0);T* tmp (T*)(::operator new((size_t)(size * sizeof(T))));if (tmp 0){cerr out of memory endl;exit(1);}return tmp;}template class Tinline void _deallocate(T* buffer){::operator delete(buffer);}template class T1,class T2inline void _construct(T1* p, const T2 value){new(p) T1(value);}template class Tinline void _destroy(T* ptr){ptr-~T();}template class Tclass allocator{public:typedef T value_type;typedef T* pointer;typedef const T* const_pointer;typedef T reference;typedef const T const_reference;typedef ptrdiff_t defference_type;//rebind allocator of type Utemplate class Ustruct rebind{typedef alloactorU other;};pointer allocate(size_type n, const void* hint 0){return _allocate(((difference_type)n, (pointer)0));}void deallocate(point p, size_type n) { _deallocate(p); }void construct(pointer p, const T value){_construct(p, value);}void destroy(point p) { _destroy(p); }pointer address(reference x) { return (pointer)x; }const_pointer const_address(const_reference x){return (const_pointer)x;}size_type max_size() const{return size_type(UINT_MAX / sizeof(T));}};}#endif //STEMMALLOC#includevector
#includeiostream
using namespace std;//main 函数中
int main_t1()
{int ia[5] { 0,1,2,3,4 };unsigned int i;vectorint, steem::allocatorint iv(ia, ia 5);for (i 0; i iv.size(); i){cout iv[i] ;}cout endl;return 0;
}
