type positive
type negative
type rec_group
type gadt
type a_arity
type b_arity
type ('a_arity, 'b_arity, 'positive, 'negative) t
val initial : (a_arity, b_arity, positive, negative) t
val grow : ('a_arity, 'b_arity, 'positive, 'negative) t -> ('a * 'a_arity, 'a * 'b_arity, _ * 'positive, _ * 'negative) t
val map : ('a_arity, 'b_arity, 'positive, 'negative) t -> ('a, 'structure, 'a_arity, rec_group, 'kinds, 'positive, 'negative, 'direct, gadt) Refl__.Desc.desc -> ('b, 'structure, 'b_arity, rec_group, 'kinds, 'positive, 'negative, 'direct, gadt) Refl__.Desc.desc -> 'a -> 'b
