Metamath Proof Explorer


Theorem bj-evalfn

Description: The evaluation at a class is a function on the universal class. (General form of slotfn ). (Contributed by Mario Carneiro, 22-Sep-2015) (Revised by BJ, 27-Dec-2021)

Ref Expression
Assertion bj-evalfn Slot 𝐴 Fn V

Proof

Step Hyp Ref Expression
1 fvex ( 𝑓𝐴 ) ∈ V
2 df-slot Slot 𝐴 = ( 𝑓 ∈ V ↦ ( 𝑓𝐴 ) )
3 1 2 fnmpti Slot 𝐴 Fn V