Performance in Halogen components

[garyb]

@thomashoneyman

It’s worth noting that if the parent has not modified the input it sends to the child, then the input is never sent. So you don’t need to care about that case.

Edit: My comment was incorrect. Input is re-sent on each parent re-render.

Yeah , the “why” for this I mentioned in the other thread:

@garyb

This guarding doesn’t happen automatically as we didn’t want to impose an Eq constraint on component state, as that is far too restrictive in general.

The same applies to the Input values, we can’t guard to see if they have changed between renders without any means of comparing them. I guess we could insert a magic reference eq check here, but I’d prefer to keep the need for the check explicit as it’s entirely predictable that way.