Theorem wl-nfnae1

Description: Unlike nfnae , this specialized theorem avoids ax-11 . (Contributed by Wolf Lammen, 27-Jun-2019)

	Ref	Expression
Assertion	wl-nfnae1	|- F/ x -. A. y y = x

Proof

Step	Hyp	Ref	Expression
1		wl-nfae1	|- F/ x A. y y = x
2	1	nfn	|- F/ x -. A. y y = x