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Re: MakeOne [message #50054 is a reply to message #47662]

Sat, 30 June 2018 14:45

Klugier
Messages: 1076
Registered: September 2012
Location: Poland, Kraków

Senior Contributor

Hello,

I have a problem with current MakeOne implementation. It doesn't work greate with auto:

One<Foo> CreateFoo() {
	auto pFoo = MakeOne<Foo>();
	
	int i = 0;
	if (i == 0) {
		return nullptr;
	}
	
	return pFoo; // Compilation error - /home/klugier/MyApps/MakeOneTest/MakeOneTest.cpp (19): error: use of deleted function 'Upp::One<T>::One(const Upp::One<T>&) [with T = Foo]'
}

The below example works as expected:

One<Foo> CreateFoo() {
	One<Foo> pFoo = MakeOne<Foo>();
	
	int i = 0;
	if (i == 0) {
		return nullptr;
	}
	
	return pFoo;
}

I am not sure it is the good design to limit it to only explicit types. std::make_shared and std::make_unique works in above case.

Sincerely,
Klugier

U++ - one framework to rule them all.

[Updated on: Sat, 30 June 2018 14:45]

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