new的故事

#include <iostream>
#include <new>
#include <cstdlib>
#define __OUTPUT_FUNC_NAME__ std::cout << __FUNCTION__ \
        <<"\tthis =\t" << this << std::endl;
 
class Foo
{
public:
    Foo()
    {
        __OUTPUT_FUNC_NAME__
    }
    virtual ~Foo()
    {
        __OUTPUT_FUNC_NAME__
    }
};
 
int main()
{
    Foo *psingle = new Foo;
    delete psingle;
 
    std::cout << __LINE__ <<std::endl;
    Foo *psingle_nothrow = new(std::nothrow) Foo();
    delete psingle_nothrow;
 
    std::cout << __LINE__ <<std::endl;
    Foo *parray = new Foo[5];
    delete[] parray;
 
    std::cout << __LINE__ <<std::endl;
    Foo *parray_nothrow = new(std::nothrow) Foo[5];
    delete[] parray_nothrow;
 
    std::cout << __LINE__ <<std::endl;
    Foo *praw = (Foo *)malloc(sizeof Foo);
    new(praw) Foo;
    praw->~Foo();
    free(praw);
 
    std::cout << __LINE__ <<std::endl;
    Foo *praw_array = (Foo *)malloc(sizeof(Foo) * 5);
    for(int i=0; i<5; ++i)
    {
        new(praw_array+i)Foo();
    }
 
    for(int i=0; i<5; ++i)
    {
        (praw_array+i)->~Foo();
    }
    free(praw_array);
 
    return 0;
}