Re: [Caml-list] ocaml 4.03 and warning 52 : argument of this constructor should not be matched against a constant pattern

[Jacques-Henri Jourdan <jacques-henri.jourdan@normalesup.org>]

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On 04/27/2016 11:36 AM, Daniel Bünzli wrote:
> Le mercredi, 27 avril 2016 à 11:22, William a écrit :
>> How are we supposed to handle this nicely with the standard library ? Is
>> there a better approach to catch those exceptions ?
> Capture them immediately around the function call that raises with a _ pattern.  
> For example:  
>
> match (try Some (List.hd lst) with Failure _ -> None) with
> | None -> Printf.printf "empty list\n"
> | Some hd -> …
>
> That's the way these functions should have been defined in the first place.
>
> Best,  
>
> Daniel
>
>
>
Or, with the new pattern matching with exception syntax :

match List.hd lst with
| exception Failure _ -> Printf.printf "empty list\n"
| hd -> ...


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