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Operator overload

Posts: n/a
Hi, just like to find out when will this operator overload function
gets triggered?

Code Snippet

class A {

enum enA {
A1, A2, A3
} value;

virtual ~A();
A::enA& operator=(const UIScsiimInitReasonCode::enA& );
operator A::enA() {

friend ostream& operator<< ( ostream&, const A&);

I know of the when will operator << and operator = be called, but I am
not sure when will the
operator A::enA() be called and what is the use (beside calling the
operator function directly like
a->operator A::enA()) ?


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Ondra Holub
Posts: n/a
It is typecast operator. So it is called when instance of A is
typecasted to A::enA (either implictly or explicitly).

Look on following code:

#include <iostream>

class A
enum enA { A1, A2, A3 };

A() { }
~A() { }

operator A::enA() { return A2; }

void Fn(A::enA e)
std::cout << "Fn(A::enA)\n";

void Fn(...)
std::cout << "Fn(...)\n";

int main()
A a;
Fn(a); // Will call Fn(A::enA) due to overload of operator A::enA()
return 0;

There are 2 overloaded functions Fn. You can guess, which one is
called, when parameter is instance of A.

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