Metamath Proof Explorer


Theorem homffn

Description: The functionalized Hom-set operation is a function. (Contributed by Mario Carneiro, 4-Jan-2017)

Ref Expression
Hypotheses homffn.f 𝐹 = ( Homf𝐶 )
homffn.b 𝐵 = ( Base ‘ 𝐶 )
Assertion homffn 𝐹 Fn ( 𝐵 × 𝐵 )

Proof

Step Hyp Ref Expression
1 homffn.f 𝐹 = ( Homf𝐶 )
2 homffn.b 𝐵 = ( Base ‘ 𝐶 )
3 eqid ( Hom ‘ 𝐶 ) = ( Hom ‘ 𝐶 )
4 1 2 3 homffval 𝐹 = ( 𝑥𝐵 , 𝑦𝐵 ↦ ( 𝑥 ( Hom ‘ 𝐶 ) 𝑦 ) )
5 ovex ( 𝑥 ( Hom ‘ 𝐶 ) 𝑦 ) ∈ V
6 4 5 fnmpoi 𝐹 Fn ( 𝐵 × 𝐵 )