Module Core_kernel.Error

This module extends Base.Error with bin_io.

type t = private Base.Info.t

Serialization and comparison force the lazy message.

val compare : t -> t -> int
val equal : t -> t -> bool
val hash_fold_t : Base.Hash.state -> t -> Base.Hash.state
val hash : t -> Base.Hash.hash_value
include Base.Sexpable.S with type t := t
val t_of_sexp : Sexplib0.Sexp.t -> t
val sexp_of_t : t -> Sexplib0.Sexp.t
val invariant : t -> unit
val to_string_hum : t -> string

to_string_hum forces the lazy message, which might be an expensive operation.

to_string_hum usually produces a sexp; however, it is guaranteed that to_string_hum (of_string s) = s.

If this string is going to go into a log file, you may find it useful to ensure that the string is only one line long. To do this, use to_string_mach t.

val to_string_mach : t -> string

to_string_mach t outputs t as a sexp on a single line.

val to_string_hum_deprecated : t -> string

Old version (pre 109.61) of to_string_hum that some applications rely on.

Calls should be replaced with to_string_mach t, which outputs more parentheses and backslashes.

val of_string : string -> t

Be careful that the body of the lazy or thunk does not access mutable data, since it will only be called at an undetermined later point.

val of_lazy : string Base.Lazy.t -> t
val of_thunk : (unit -> string) -> t
val of_lazy_t : t Base.Lazy.t -> t
val create : ?here:Caml.Lexing.position -> ?strict:unit -> string -> 'a -> ('a -> Base.Sexp.t) -> t

For create message a sexp_of_a, sexp_of_a a is lazily computed, when the info is converted to a sexp. So if a is mutated in the time between the call to create and the sexp conversion, those mutations will be reflected in the sexp. Use ~strict:() to force sexp_of_a a to be computed immediately.

val create_s : Base.Sexp.t -> t
val createf : ('a, unit, string, t) format4 -> 'a

Constructs a t containing only a string from a format. This eagerly constructs the string.

val tag : t -> tag:string -> t

Adds a string to the front.

val tag_s : t -> tag:Base.Sexp.t -> t

Adds a sexp to the front.

val tag_arg : t -> string -> 'a -> ('a -> Base.Sexp.t) -> t

Adds a string and some other data in the form of an s-expression at the front.

val of_list : ?trunc_after:int -> t list -> t

Combines multiple infos into one.

val of_exn : ?backtrace:[ `Get | `This of string ] -> exn -> t

of_exn and to_exn are primarily used with Error, but their definitions have to be here because they refer to the underlying representation.

~backtrace:`Get attaches the backtrace for the most recent exception. The same caveats as for Printexc.print_backtrace apply. ~backtrace:(`This s) attaches the backtrace s. The default is no backtrace.

val to_exn : t -> exn
val pp : Base.Formatter.t -> t -> unit
module Internal_repr : sig ... end
val raise : t -> _

Note that the exception raised by this function maintains a reference to the t passed in.

val raise_s : Base.Sexp.t -> _
val to_info : t -> Base.Info.t
val of_info : Base.Info.t -> t

This include is the source of the bin_io functions.

include Bin_prot.Binable.S with type t := t
include Bin_prot.Binable.S_only_functions with type t := t
val bin_size_t : t Bin_prot.Size.sizer
val bin_write_t : t Bin_prot.Write.writer
val bin_read_t : t Bin_prot.Read.reader
val __bin_read_t__ : (int -> t) Bin_prot.Read.reader

This function only needs implementation if t exposed to be a polymorphic variant. Despite what the type reads, this does *not* produce a function after reading; instead it takes the constructor tag (int) before reading and reads the rest of the variant t afterwards.

val bin_shape_t : Bin_prot.Shape.t
val bin_writer_t : t Bin_prot.Type_class.writer
val bin_reader_t : t Bin_prot.Type_class.reader
module Stable : sig ... end

Error.t is not wire-compatible with Error.Stable.V1.t. See info.mli for details.

val failwiths : ?strict:Base.Unit.t -> here:Lexing.position -> Base.String.t -> 'a -> ('a -> Base.Sexp.t) -> _
failwiths ?strict ~here message a sexp_of_a
= Error.raise (Error.create ?strict ~here s a sexp_of_a)

As with Error.create, sexp_of_a a is lazily computed when the error is converted to a sexp. So if a is mutated in the time between the call to failwiths and the sexp conversion, those mutations will be reflected in the error message. Use ~strict:() to force sexp_of_a a to be computed immediately.

In this signature we write ~here:Lexing.position rather than ~here:Source_code_position.t to avoid a circular dependency.

val failwithp : ?strict:Base.Unit.t -> Lexing.position -> Base.String.t -> 'a -> ('a -> Base.Sexp.t) -> _