Metamath Proof Explorer


Theorem hmeofn

Description: The set of homeomorphisms is a function on topologies. (Contributed by Mario Carneiro, 23-Aug-2015)

Ref Expression
Assertion hmeofn Homeo Fn Top × Top

Proof

Step Hyp Ref Expression
1 df-hmeo Homeo = j Top , k Top f j Cn k | f -1 k Cn j
2 ovex j Cn k V
3 2 rabex f j Cn k | f -1 k Cn j V
4 1 3 fnmpoi Homeo Fn Top × Top