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