Section BigSetOps.
Variables T I : finType.
Implicit Types (U : {pred T}) (P : pred I) (A B : {set I}) (F :  I -> {set T}).
End Curry.

Lemma imset_cover (T' : finType) P  (f : T -> T') :
[set f x | x in cover P] = \bigcup_(i in P) [set f x | x in i].