ℤ-rng ∈ IntegDom{i}
{ MemTypeCD⋅ }
ℤ-rng ∈ CRng
.....set predicate.....
IsIntegDom(ℤ-rng)
.....wf.....
1. r : CRng
⊢ IsIntegDom(r) ∈ Type