Checking if path-pieces overlap

[KommuSoft]

Would it make sense that the path pieces have a method that provides a regular expression that matches (at least) all possible values.

In that case we can determine an intersection finite-state machine and if this minimizes to an FSM that accepts no input at all, we know that the two patterns can never overlap.

[snoyberg]

That seems like a large departure from the current API.