Generation by a predicate, for packed generators that have not yet been reified as an array of permutations. Words use left-action composition.
- id {n : Nat} {S : Perm n → Prop} : Span S (Perm.id n)
- mul_left {n : Nat} {S : Perm n → Prop} {a b : Perm n} : S a → Span S b → Span S (a.comp b)
- inv_mul_left {n : Nat} {S : Perm n → Prop} {a b : Perm n} : S a → Span S b → Span S (a.inv.comp b)