C ++这个指针，在函数调用中隐藏参数 [英] C++ this pointer, hidden argument in function calls

问题描述

我有一个堆栈类的成员和一个函数叫push。

I have a stack class with members and a function called push.

class STACK
{
    int data;
    public:
    void push(int x)
    {
        data=x;
    }
}

C ++如何转换此语句： p>

What does C++ do to convert this statement:

s1.push(3);

到

s1.push(this,3);

基本上我的问题是发生在生成 code>指针并将其作为隐藏参数传递？

Basically my question is what happens under the hood to generate the this pointer and pass it as a hidden argument?

我实际上是在C编码。我的目标是有一个程序，可能。对于这个我有功能指针作为结构的成员。因此，我想知道是否可能以某种方式跟踪哪个结构称为函数（像this指针）。我不想做像：s1.push（& s1,3）;因为它击败了我的目的。

I am actually coding in C. My objective is to have a program which is as close to OOP as possible. For this i have function pointers as members of the structure. Therefore, I want to know if it is possible to somehow have track of which structure called the function (like a "this" pointer ). I don't want to do something like: s1.push(&s1,3); because it beats my purpose.

它可以转换s1.push（3）;到s1.push（& 1,3）;通过MACRO替换

推荐答案

语句：

s1.push(3);

未翻译为

 s1.push(this, 3);

但是类似这样：

STACK::push(&s1, 3); 

其中 STACK :: push 作为全局/命名空间或静态函数在类/命名空间 STACK 下，其原型将是：

Where STACK::push may be treated as global/namespace or static function under class/namespace STACK, whose prototype would be:

push(STACK const* pThis, int arg);

this 指针总是第一个参数到方法（函数）。如果方法有零参数，它仍然有一个参数（这个类的指针）。

The this pointer is always the first argument to the method (function). If method has zero argument, it will still have one argument (the this pointer of class).

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