how to iterate over an AA by key-value pair (tuple)?

[Timothee Cour]

how to iterate over an AA by key-value pair (tuple)?
use case:
avoid interrupting UFCS chains, eg:
foo.generate_aa.byKeyValue.filter!(a=>a[0].isLower).map!(a=>a[1]) ...
of course I could roll my own function but I was wondering if there's
already a way.