Support rank

[eygraber]

I've run into some scenarios where I can't use replaces because my test module doesn't have access to my impl module. It would be helpful if rank was available.

[vRallev]

I'm hesitant. I never liked this API in the original Anvil and we only added it because of Square's opinionated module structure. I think an exclude on the component works better and keeps it more explicit if you cannot use replaces.

[eygraber]

Is it the specific rank API, or the overall idea? If the former, what about specifying that this should replace any type bound to the boundType (i.e. same outcome but different semantics)?

[vRallev]

The rank API in general, because it only worked for ContributesBinding and not ContributesTo for example. This very loose coupling could also lead to negative surprises.

what about specifying that this should replace any type bound to the boundType (i.e. same outcome but different semantics)?

This basically restricts the rank integer to 0 and 1. Very soon the first person will ask for 0, 1 and 2 🙃