Theorem funtopon 23060

Description: The class TopOn is a function. (Contributed by BJ, 29-Apr-2021.)

Assertion

Ref	Expression
funtopon	⊢ Fun TopOn

Proof of Theorem funtopon

Dummy variables 𝑥 𝑦 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		df-topon 23051	. 2 ⊢ TopOn = (𝑦 ∈ V ↦ {𝑥 ∈ Top ∣ 𝑦 = ∪ 𝑥})
2	1	funmpt2 6579	1 ⊢ Fun TopOn

Syntax hints:   = wceq 1568  {crab 3423  Vcvv 3462  ∪ cuni 4877  Fun wfun 6534  Topctop 23033  TopOnctopon 23050

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1823  ax-4 1837  ax-5 1938  ax-6 1995  ax-7 2036  ax-8 2152  ax-9 2160  ax-10 2183  ax-11 2199  ax-12 2220  ax-ext 2742  ax-sep 5262  ax-pr 5408

This theorem depends on definitions:  df-bi 210  df-an 401  df-or 861  df-3an 1103  df-tru 1571  df-fal 1581  df-ex 1808  df-nf 1812  df-sb 2099  df-mo 2574  df-eu 2604  df-clab 2749  df-cleq 2762  df-clel 2845  df-nfc 2919  df-ral 3087  df-rex 3097  df-rab 3424  df-v 3464  df-dif 3916  df-un 3918  df-in 3920  df-ss 3930  df-nul 4295  df-if 4493  df-sn 4595  df-pr 4597  df-op 4601  df-br 5115  df-opab 5179  df-mpt 5198  df-id 5560  df-xp 5671  df-rel 5672  df-cnv 5673  df-co 5674  df-fun 6542  df-topon 23051

This theorem is referenced by:  fntopon  23064  toprntopon  23065