Metamath Proof Explorer


Theorem 0func

Description: The functor from the empty category. (Contributed by Zhi Wang, 7-Oct-2025) (Proof shortened by Zhi Wang, 17-Oct-2025)

Ref Expression
Hypothesis 0func.c φ C Cat
Assertion 0func φ Func C =

Proof

Step Hyp Ref Expression
1 0func.c φ C Cat
2 0ex V
3 2 a1i φ V
4 base0 = Base
5 4 a1i φ = Base
6 3 5 1 0funcg φ Func C =