include Sig.X
val type_info : r -> Ty.tval str_cmp : r -> r -> intval hash_cmp : r -> r -> intval equal : r -> r -> boolval subst : r -> r -> r -> rval solve : r -> r -> (r * r) listval is_a_leaf : r -> boolval abstract_selectors : r -> (r * r) list -> r * (r * r) listval assign_value : r -> r list -> (Expr.t * r) list -> (Expr.t * bool) option