Re: [Caml-list] try with

[Dave Benjamin <dave@ramenlabs.com>]

On Sun, 5 Aug 2007, tmp123@menta.net wrote:

> Sorry for an easy question about exceptions:
>
> If in a code like:
>
> let v1 = f1 () in
> f2 v1
>
> I like to handle in a different way an exception (like Not_found) 
> produced inside f1 of the same one produced in f2 (or even not treat the 
> one produced in f2), which one is a correct way to write the code?

One way (besides the exception technique you posted) is to convert the 
exception to an option or other variant:

let maybe_v1 = try Some (f1 ()) with Not_found -> None in
match maybe_v1 with
   | Some v1 -> f2 v1
   | None -> handle_f1_exception ()

Also see the following page for a "let try" syntax extension:

http://martin.jambon.free.fr/extend-ocaml-syntax.html#lettry