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Date: Tue, 10 Jun 2003 17:28:57 +0200
Subject: Re: [Caml-list] polymorphic type constructor deconstructor
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Cc: caml-list@inria.fr
To: "Jeffrey J. Cook" <jjcook@uiuc.edu>
From: Damien Doligez <Damien.Doligez@inria.fr>
In-Reply-To: <20030606213021.GE27432@crhc.uiuc.edu>
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On Friday, June 6, 2003, at 11:30 PM, Jeffrey J. Cook wrote:

> let request = REQ_do_this 5 in
> let reply = Socket.client "mysocket" request in
> let success =
>   match reply with
>   | REPLY_do_this x -> x
>   | _ -> failwith "this case shouldn't happen and is annoying"

You can use patterns in the left-hand part of a let:

let request = REQ_do_this 5 in
let reply = Socket.client "mysocket" request in
let REPLY_do_this success = reply in
... success ...

The compiler will complain about a non-exhaustive pattern matching,
but that's only fair.

-- Damien

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