what is the meaning of this syntax

Question

The following code compiles. But if I write the code to call the method test using jar it is giving me a compilation error. What is really happening here.

#include <iostream>    

using namespace std;

class A {
public:
  void test() {
    cout << "working" << endl;
  }
};

int main() {
  A foo;
  A jar();
}

That's not a variable declaration. – chris Apr 01 '13 at 22:25 — chris, Apr 01 '13 at 22:25
http://en.wikipedia.org/wiki/Most_vexing_parse – Pubby Apr 01 '13 at 22:25 — Pubby, Apr 01 '13 at 22:25

taocp · Accepted Answer · 2013-04-01T22:33:33.560

7

 A jar();

declares a function named jar without any parameters, and return type is object of class A.

You cannot declare a function inside main, therefore, you got the error.

edited Apr 01 '13 at 22:33

answered Apr 01 '13 at 22:28

taocp

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It's not really the MVP (`SomeType var(SomeClass());`), but close enough. You can declare the function, but you can't use it like an object. – chris Apr 01 '13 at 22:30

0x90 · Answer 2 · 2013-04-02T11:31:00.957

1

If you tried to declare a function pointer named ptr you should declare it like that:

A (*ptr)(void);

edited Apr 02 '13 at 11:31

answered Apr 01 '13 at 22:31

0x90

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what is the meaning of this syntax

2 Answers2