pmap -package:typerep-map -is:exact package:plutarch-extra -is:exact

pmapWithKey :: forall (k :: PType) (a :: PType) (b :: PType) (keysort :: KeyGuarantees) (s :: S) . (PIsData k, PIsData a, PIsData b) => Term s ((k :--> (a :--> b)) :--> (PMap keysort k a :--> PMap 'Unsorted k b))
plutarch-extra Plutarch.Extra.Map
Like regular fmap but it provides key of each element that is being modified.