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