Why not infer template parameter from constructor?

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I think it is not valid because the constructor isn’t always the only point of entry of the class (I am talking about copy constructor and operator=). So suppose you are using your class like this :

MyClass m(string s);
MyClass *pm;
*pm = m;

I am not sure if it would be so obvious for the parser to know what template type is the MyClass pm;

Not sure if what I said make sense but feel free to add some comment, that’s an interesting question.

C++ 17

It is accepted that C++17 will have type deduction from constructor arguments.

Examples:

std::pair p(2, 4.5);
std::tuple t(4, 3, 2.5);

Accepted paper.

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