module Netexn:sig..end
Exception registry
This module allow the user to register exceptions, and to set a
custom exception printing function. This results in nicer exception
prints when Netexn.to_string is called instead of Printexc.to_string.
Generally, Printexc.to_string works well if:
In these cases it is not required to register a custom printer. Arguments that are neither int nor string are printed as "_", however, so defining a custom printer helps then.
The printers registered here are intended for helping debugging, so the goal is to print all of the exception in an unambiguous way. The syntax "Exception(arg1, arg2, ...)" is preferred.
Since OCaml 3.11.2 there is a similar feature in Printexc.
If Ocamlnet recognizes that Printexc.register_printer is available,
all functions registered in this module are also registered at
the central Printexc registry. For users it does not make a difference
then whether Netexn.to_string or Printexc.to_string is called
to print the exception. We recommend, however, to use Netexn as
primary registry for all code that uses Ocamlnet because this
mechanism also works for older Ocaml versions, and is slightly more
efficient.
val register_printer : exn -> (exn -> string) -> unitregister e f: Register that the exception type of the sample
exception e is to be printed by f.
In multi-threaded programs, this function should no longer be called once threads have been spawned.
val to_string : exn -> stringPrints the exception as string, using the registered printer functions,
or Printexc.to_string as fallback if there is no better printer