type constant =| Const_int of int| Const_char of char| Const_string of string * string option| Const_float of string| Const_int32 of int32| Const_int64 of int64| Const_nativeint of nativeinttype rec_flag =| Nonrecursive| Recursivetype direction_flag =| Upto| Downtotype private_flag =| Private| Publictype mutable_flag =| Immutable| Mutabletype virtual_flag =| Virtual| Concretetype override_flag =| Override| Freshtype closed_flag =| Closed| Opentype label = stringtype arg_label =| Nolabel| Labelled of string| Optional of stringtype 'a loc = 'a Location.loc = {txt : 'a;loc : Location.t;}type variance =| Covariant| Contravariant| Invariant