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Message-ID: <4DBC3AF0.4010402@gmail.com>
Date: Sat, 30 Apr 2011 18:38:08 +0200
From: Andrew <newsgroups.fr@gmail.com>
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To: Jon Harrop <jon@ffconsultancy.com>
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Subject: Re: [Caml-list] Comparing variant types

On Apr. 29, 2011, Jon Harrop <jon@ffconsultancy.com> wrote:
> Andrew wrote:
>> Why not write directly
>> 	let dir_equal = fun d1 d2 ->
>> 	| Left Left
>> 	  | Right Right
>> 	  | Up Up
>> 	  | Down Down
>> 	  | No_op No_op ->   true
>> 	  | _ ->  false
>
> You want to fill out your _ pattern with explicit type constructors
> otherwise it is fragile wrt new constructors being added to the type.

Oh, ok =)

> Cheers,
> Jon.