问题描述
这两个声明有什么区别:
What is the difference between these 2 declaration:
int operate(int (*func)(int, int), int a, int b){
return (*func)(a, b);
}
和
int operate(int func(int, int), int a, int b){
return func(a, b);
}
这两个似乎也等效:operate(sum, 1, 1)和operate(&sum, 1, 1)
These two also seems to be equivalent: operate(sum, 1, 1) and operate(&sum, 1, 1)
如果我将函数sum作为2个数字的函数传递给func，则结果仍然相同.为什么?
If I pass function sum as a function of 2 numbers in the place of func, the result are still the same. Why?
推荐答案
§6.7.5.3/8:
§6.7.5.3/8:
换句话说，两个函数声明是相同的.
In other words, the two function declarations are identical.
就函数调用而言，第6.5.2.2/3节:
As far as the function call goes, §6.5.2.2/3:
由于func(a, b);和(*func)(a, b)都是后缀表达式，后跟括号，因此它们都是函数调用.由于func和(*func)都指定相同的功能，因此它们都调用相同的功能.
Since both func(a, b); and (*func)(a, b) are postfix expressions followed by parentheses, they're both function calls. Since func and (*func) both designate the same function, they both call the same function.
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