Exceptions.
sexp_of_t
uses a global table of sexp converters. To register a converter for a new
exception, add [@@deriving_inline sexp][@@@end]
to its definition. If no suitable converter is
found, the standard converter in Printexc
will be used to generate an atomic
S-expression.
include sig ... end
val sexp_of_t : t ‑> Base.Sexp.t
Raised when finalization after an exception failed, too. The first exception argument is the one raised by the initial function, the second exception the one raised by the finalizer.
exception
Reraised of string * t
val create_s : Base.Sexp.t ‑> t
create_s sexp
returns an exception t
such that phys_equal (sexp_of_t t) sexp
.
This is useful when one wants to create an exception that serves as a message and the
particular exn constructor doesn't matter.
val reraise : t ‑> string ‑> _
val reraisef : t ‑> ('a, unit, string, unit ‑> _) Pervasives.format4 ‑> 'a
Types with format4
are hard to read, so here's an example.
let foobar str =
try
...
with exn ->
Exn.reraisef exn "Foobar is buggy on: %s" str ()
val protectx : f:('a ‑> 'b) ‑> 'a ‑> finally:('a ‑> unit) ‑> 'b
Executes f
and afterwards executes finally
, whether f
throws an exception or
not.
val handle_uncaught : exit:bool ‑> (unit ‑> unit) ‑> unit
handle_uncaught ~exit f
catches an exception escaping f
and prints an error
message to stderr. Exits with return code 1 if exit
is true
, and returns unit
otherwise.
Note that since OCaml 4.02.0, you don't need to use this at the entry point of your program, as the OCaml runtime will do better than this function.
val handle_uncaught_and_exit : (unit ‑> 'a) ‑> 'a
handle_uncaught_and_exit f
returns f ()
, unless that raises, in which case it
prints the exception and exits nonzero.
val reraise_uncaught : string ‑> (unit ‑> 'a) ‑> 'a
Traces exceptions passing through. Useful because in practice, backtraces still don't seem to work.
Example:
let rogue_function () = if Random.bool () then failwith "foo" else 3
let traced_function () = Exn.reraise_uncaught "rogue_function" rogue_function
traced_function ();;
: Program died with Reraised("rogue_function", Failure "foo")