85 lines
3.8 KiB
OCaml
85 lines
3.8 KiB
OCaml
(***********************************************************************)
|
|
(* *)
|
|
(* OCaml *)
|
|
(* *)
|
|
(* Xavier Leroy, projet Cristal, INRIA Rocquencourt *)
|
|
(* *)
|
|
(* Copyright 1996 Institut National de Recherche en Informatique et *)
|
|
(* en Automatique. All rights reserved. This file is distributed *)
|
|
(* under the terms of the GNU Library General Public License, with *)
|
|
(* the special exception on linking described in file ../LICENSE. *)
|
|
(* *)
|
|
(***********************************************************************)
|
|
|
|
(** Facilities for printing exceptions. *)
|
|
|
|
val to_string: exn -> string
|
|
(** [Printexc.to_string e] returns a string representation of
|
|
the exception [e]. *)
|
|
|
|
val print: ('a -> 'b) -> 'a -> 'b
|
|
(** [Printexc.print fn x] applies [fn] to [x] and returns the result.
|
|
If the evaluation of [fn x] raises any exception, the
|
|
name of the exception is printed on standard error output,
|
|
and the exception is raised again.
|
|
The typical use is to catch and report exceptions that
|
|
escape a function application. *)
|
|
|
|
val catch: ('a -> 'b) -> 'a -> 'b
|
|
(** [Printexc.catch fn x] is similar to {!Printexc.print}, but
|
|
aborts the program with exit code 2 after printing the
|
|
uncaught exception. This function is deprecated: the runtime
|
|
system is now able to print uncaught exceptions as precisely
|
|
as [Printexc.catch] does. Moreover, calling [Printexc.catch]
|
|
makes it harder to track the location of the exception
|
|
using the debugger or the stack backtrace facility.
|
|
So, do not use [Printexc.catch] in new code. *)
|
|
|
|
val print_backtrace: out_channel -> unit
|
|
(** [Printexc.print_backtrace oc] prints an exception backtrace
|
|
on the output channel [oc]. The backtrace lists the program
|
|
locations where the most-recently raised exception was raised
|
|
and where it was propagated through function calls.
|
|
@since 3.11.0
|
|
*)
|
|
|
|
val get_backtrace: unit -> string
|
|
(** [Printexc.get_backtrace ()] returns a string containing the
|
|
same exception backtrace that [Printexc.print_backtrace] would
|
|
print.
|
|
@since 3.11.0
|
|
*)
|
|
|
|
val record_backtrace: bool -> unit
|
|
(** [Printexc.record_backtrace b] turns recording of exception backtraces
|
|
on (if [b = true]) or off (if [b = false]). Initially, backtraces
|
|
are not recorded, unless the [b] flag is given to the program
|
|
through the [OCAMLRUNPARAM] variable.
|
|
@since 3.11.0
|
|
*)
|
|
|
|
val backtrace_status: unit -> bool
|
|
(** [Printexc.backtrace_status()] returns [true] if exception
|
|
backtraces are currently recorded, [false] if not.
|
|
@since 3.11.0
|
|
*)
|
|
|
|
val register_printer: (exn -> string option) -> unit
|
|
(** [Printexc.register_printer fn] registers [fn] as an exception
|
|
printer. The printer should return [None] or raise an exception
|
|
if it does not know how to convert the passed exception, and [Some
|
|
s] with [s] the resulting string if it can convert the passed
|
|
exception. Exceptions raised by the printer are ignored.
|
|
|
|
When converting an exception into a string, the printers will be invoked
|
|
in the reverse order of their registrations, until a printer returns
|
|
a [Some s] value (if no such printer exists, the runtime will use a
|
|
generic printer).
|
|
|
|
When using this mechanism, one should be aware that an exception backtrace
|
|
is attached to the thread that saw it raised, rather than to the exception
|
|
itself. Practically, it means that the code related to [fn] should not use
|
|
the backtrace if it has itself raised an exception before.
|
|
@since 3.11.2
|
|
*)
|