module Error: Errorinclude Info
val raise : t -> 'aval to_info : t -> Info.tval of_info : Info.t -> tval failwiths : string -> 'a -> ('a -> Sexplib.Sexp.t) -> 'bfailwiths message value sexp_of_value raises an exception with the supplied
    message and value, by constructing an Error.t and using Error.raise.  As
    usual, the sexp_of_value is only applied when the value is converted to a sexp or a
    string.  So, if you mutate value in between the time you call failwiths and the
    time the error is displayed, those mutations will be reflected in the error message.
    failwiths s a f = Error.raise (Error.create s a f)
    failwithp _here_ s a f is just failwiths with the source code position tagged on.
    We use Lexing.position rather than Source_code_position.t to avoid a circular
    dependency.
val failwithp : Lexing.position -> string -> 'a -> ('a -> Sexplib.Sexp.t) -> 'b