Metamath Proof Explorer


Theorem funcnv0

Description: The converse of the empty set is a function. (Contributed by AV, 7-Jan-2021)

Ref Expression
Assertion funcnv0 Fun

Proof

Step Hyp Ref Expression
1 fun0 Fun ∅
2 cnv0 ∅ = ∅
3 2 funeqi ( Fun ∅ ↔ Fun ∅ )
4 1 3 mpbir Fun