Metamath Proof Explorer


Theorem fsetex

Description: The set of functions between two classes exists if the codomain exists. Generalization of mapex to arbitrary domains. (Contributed by AV, 14-Aug-2024)

Ref Expression
Assertion fsetex B V f | f : A B V

Proof

Step Hyp Ref Expression
1 mapfset B V f | f : A B = B A
2 ovex B A V
3 1 2 eqeltrdi B V f | f : A B V