What does a constructor return?

c++ constructor return-type
Invisible Hulk picture Invisible Hulk · Nov 23, 2010 · Viewed 19.2k times · Source

My question is what does a constructor return? This question is not quite different from "What is the return type of a constructor?" I have read somewhere that a constructor returns a complete object implicitly (i.e implicit return type is the name of the class) but it shall not be specified explicitly.

struct empty{};

int main(){
   empty(); //creates a temporary and implicitly a constructor is called
}

So as per my interpretation the implicit return type should be the name of the class, in this case empty. Is my wild interpretation correct?

Answer

James McNellis picture James McNellis · Nov 23, 2010

A constructor doesn't return anything. A constructor is called to initialize an object. A constructor can only be used to initialize an object; you can't actually call a constructor explicitly (for one thing, constructors do not have names).

In the example you give, empty() is not a function call expression, it is value initialization. It creates a value-initialized temporary object of type empty.

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