Theorem isdmn

Description: Obsolete theorem, use isidom2 instead. The predicate "is a domain". (Contributed by Jeff Madsen, 10-Jun-2010) (Proof modification is discouraged.) (New usage is discouraged.)

	Ref	Expression
Assertion	isdmn	|- ( R e. Dmn <-> ( R e. PrRing /\ R e. Com2 ) )

Proof

Step	Hyp	Ref	Expression
1		df-dmn	|- Dmn = ( PrRing i^i Com2 )
2	1	elin2	|- ( R e. Dmn <-> ( R e. PrRing /\ R e. Com2 ) )