Theorem funtopon 20947

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 20938	. 2 ⊢ TopOn = (𝑦 ∈ V ↦ {𝑥 ∈ Top ∣ 𝑦 = ∪ 𝑥})
2	1	funmpt2 6088	1 ⊢ Fun TopOn

Syntax hints:   = wceq 1632  {crab 3054  Vcvv 3340  ∪ cuni 4588  Fun wfun 6043  Topctop 20920  TopOnctopon 20937

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1871  ax-4 1886  ax-5 1988  ax-6 2054  ax-7 2090  ax-9 2148  ax-10 2168  ax-11 2183  ax-12 2196  ax-13 2391  ax-ext 2740  ax-sep 4933  ax-nul 4941  ax-pr 5055

This theorem depends on definitions:  df-bi 197  df-or 384  df-an 385  df-3an 1074  df-tru 1635  df-ex 1854  df-nf 1859  df-sb 2047  df-eu 2611  df-mo 2612  df-clab 2747  df-cleq 2753  df-clel 2756  df-nfc 2891  df-ral 3055  df-rab 3059  df-v 3342  df-dif 3718  df-un 3720  df-in 3722  df-ss 3729  df-nul 4059  df-if 4231  df-sn 4322  df-pr 4324  df-op 4328  df-br 4805  df-opab 4865  df-mpt 4882  df-id 5174  df-xp 5272  df-rel 5273  df-cnv 5274  df-co 5275  df-fun 6051  df-topon 20938

This theorem is referenced by:  fntopon  20950  toprntopon  20951