Theorem csbconstg

Description: Substitution doesn't affect a constant B (in which x does not occur). csbconstgf with distinct variable requirement. (Contributed by Alan Sare, 22-Jul-2012)

	Ref	Expression
Assertion	csbconstg	$$⊢A\in V\to ⦋A/x⦌B=B$$

Proof

Step	Hyp	Ref	Expression
1		nfcv	$$⊢\underset{\_}{Ⅎ}xB$$
2	1	csbconstgf	$$⊢A\in V\to ⦋A/x⦌B=B$$