c++ stl 分析

这个是讲配置器

#pragma once/*这个是看候捷stl 源码解析 的配置器，以下为对应代码*/#ifndef _JJALLOC_#define _JJALLOC_#include <new>#include <cstddef>#include <cstdlib>#include <climits>#include <iostream>namespace JJ{    template<class T>    inline 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 T>    inline void _deallocate(T* buffer)    {        ::operator delete(buffer);    }    template <class T1, class T2>    inline void _construct(T1 *p, const T2&value)    {        new(p) T1(value);    }    template<class T>    inline void _destroy(T* ptr)    {        ptr->~T();    }    template<class T>    class allocator    {    public:        allocator();        ~allocator();        typedef T value_type;        typedef T* pointer;        typedef const T* const_pointer;        typedef T& reference;        typedef const T& const_reference;        typedef size_t size_type;        typedef ptrfdiff_t difference_type;        template<class U>        struct rebind        {            typedef allocator<U> other;        };        pointer allocate(size_type n, const void *hint = 0)        {            return _allocate((difference_type)n, (pointer)0);        }        void deallocate(pointer p, size_type n)        {            _deallocate(p);        }        void construct(pointer p, const T& value)        {            _construct(p, value);        }        void destroy(pointer 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));        }    private:    };}#endif