fact: Definition fset_map `(f : A → B) `{SetType A} `{SetType B} `{EmptySet B} `{SetJoin B} `{SetSingleton B} `{U : !FSetExtend A} : set_type A → set_type B := fset_extend (singleton ∘ f).
imports: MathClasses.interfaces.abstract_algebra MathClasses.interfaces.orders