The *-ring structure on suitable quotients of a *-ring. #
@[instance_reducible]
def RingQuot.starRing {R : Type u} [Semiring R] [StarRing R] (r : R → R → Prop) (hr : ∀ (a b : R), r a b → r (star a) (star b)) :
Transfer a StarRing instance through a quotient, if the quotient is invariant to star
Equations
- RingQuot.starRing r hr = { star := RingQuot.star'✝ r hr, star_involutive := ⋯, star_mul := ⋯, star_add := ⋯ }