Theorem icheqid

Description: In an equality for the same setvar variable, the setvar variable is interchangeable by itself. Special case of ichid and icheq without distinct variables restriction. (Contributed by AV, 29-Jul-2023)

	Ref	Expression
Assertion	icheqid	|- [ x <> x ] x = x

Proof

Step	Hyp	Ref	Expression
1		ichid	|- [ x <> x ] x = x