Clean up existing data in move assignment operator

[dsnopek]

I need some advice on this one from someone with stronger modern C++ knowledge than me.

While trying to find the source of the memory leak in issue #1240, I noticed that the move assignment operator on variant types is not cleaning up any pre-existing data, for example, in Array, there was:

Array &Array::operator=(Array &&other) {
	std::swap(opaque, other.opaque);
	return *this;
}

If opaque already contained a valid array, this seems like it would swap it for the data in other.opaque, without ever cleaning up the pre-existing data in opaque.

Does this make sense? Or, am I just misunderstanding these new fangled rvalue references and move operations?

Marking as a draft because I don't know if this makes sense

(PS: This is NOT the source of the memory leak in #1240 as my PR doesn't fix it.)

[dsnopek]

Or, is this ok because std::swap() will have put the contents of opaque into other.opaque and since other is temporary, we can depend on its destructor leading to the data getting cleaned up?

[mihe]

Or, is this ok because std::swap() will have put the contents of opaque into other.opaque and since other is temporary, we can depend on its destructor leading to the data getting cleaned up?

This is correct. The changes in this PR shouldn't be needed.

[dsnopek]

Ah, ok, thanks!