type type_mismatch = | Arity| Privacy| Kind| Constraint| Manifest| Variance| Field_type of Ident.t| Field_mutable of Ident.t| Field_arity of Ident.t| Field_names of int * Ident.t * Ident.t| Field_missing of bool * Ident.t| Record_representation of bool| Unboxed_representation of bool| Immediate