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2. 操作者无效* 和操作者ool
原标题:define both operator void* and operator bool

我试图创建一个包含一个<代码>operator bool和一个operator void*的类别,但汇编者说,这些等级是模棱两可的。 我是否可以向汇编者解释哪些操作者使用,或者我是否没有使用这两者?

class A {
public:
    operator void*(){
        cout << "operator void* is called" << endl;
        return 0;
    }

    operator bool(){
        cout << "operator bool is called" << endl;
        return true;
    }
};

int main()
{
    A a1, a2;
    if (a1 == a2){
        cout << "hello";
    }
} 
最佳回答

你可以直接打电话给经营者。

int main()
{
    A a1, a2;
    if (static_cast<bool>(a1) == static_cast<bool>(a2)){
        cout << "hello";
    }
} 

但是,在这种情况下,它想像你那样界定<代码>operator=(,而不是取决于换算。

问题回答

这里的问题是,你重新定义了<代码>operator bool,但从您希望使用的密码operator =。 或者,你可以明确加入<代码>,删除*,如:

if ((void *)a1 == (void *)a2) {
    // ...
}

......但这确实是荒谬的。 不要这样做。 相反,将<代码>operator ==界定为,如载于上。

bool operator==(const A& other) const {
    return /* whatever */;
}




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