fact: Definition op_closed_proper: ∀ (Pproper: ∀ s x x', x = x' → iffT (P s x) (P s x')) o, ∀ x x', x = x' → iffT (@op_closed o x) (@op_closed o x').
imports: Coq.Classes.RelationClasses MathClasses.interfaces.universal_algebra MathClasses.theory.ua_homomorphisms MathClasses.theory.categories MathClasses.interfaces.abstract_algebra