[aidos]

I don't know the internal details but that sort of abuse of the key attribute seems like a dangerous thing to rely on.

I'll assume your key is quick to calculate. If a prop change causes the hash / key to change then react doesn't know how to reuse the dom fragment. I guess it will just reuse the stuff that's in the same location in that case so maybe it's fine. You'll lose the advantage that keys give you in the first case which is dealing with reordering.

And actually, just because the key changes or not, that doesn't cause a rerender or not. The rerender is always going to happen. Right? Unless I'm missing something.