> This is like trying to defend that you can't statically know the result of 1 + 2

It is completely unlike that. tsimionescu is asserting that they can always know statically whether `foo` will move its parameter. The function I provided is a counter-example to that assertion.

Of course the branch body always moves, that's what it's there for. That has no bearing on the argument.

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charcircuit 2 hours ago | parent [-]

>Of course the branch body always moves

>That has no bearing on the argument.

That is the whole argument. Let me quote the other person: "My claim is that, if I call `foo(std::move(myObj))`, it is statically knowable if `foo` receives a copy of `myObj` or whether it is moved to it."

It is saying that for "auto pp = std::move(p);" we will know if it uses the move assign constructor or the copy assign constructor.

	▲	masklinn 34 minutes ago \| parent [-]
		> That is the whole argument No, it is not. > Let me quote the other person: "My claim is that, if I call `foo(std::move(myObj))`, it is statically knowable if `foo` receives a copy of `myObj` or whether it is moved to it." Yes. `foo`. > It is saying that for "auto pp = std::move(p);" we will know if it uses the move assign constructor or the copy assign constructor. `pp` is not `foo`. That `pp` uses a move constructor is not the subject of the debate. You can literally take the function I posted, build a bit of scaffolding around it, and observe that whether the parameter is moved into `foo` or not is runtime behaviour: https://godbolt.org/z/jrPKhP35s