Theorem relwdom

Description: Weak dominance is a relation. (Contributed by Stefan O'Rear, 11-Feb-2015)

	Ref	Expression
Assertion	relwdom	$$⊢\mathrm{Rel}{\preccurlyeq }^{*}$$

Proof

Step	Hyp	Ref	Expression
1		df-wdom	$$⊢{\preccurlyeq }^{*}=\left\{⟨x,y⟩|\left(x=\varnothing \vee \exists zz:y\underset{onto}{⟶}x\right)\right\}$$
2	1	relopabi	$$⊢\mathrm{Rel}{\preccurlyeq }^{*}$$