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From: "Matej Košík" <mail@matej-kosik.net>
To: caml-list@inria.fr
Subject: [Caml-list] beginner question about pattern matching
Date: Thu, 19 Oct 2017 15:38:27 +0200	[thread overview]
Message-ID: <72565dd8-08e0-0fd3-a3df-6742e1957ec3@matej-kosik.net> (raw)


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Hi,

I am trying to do simple pattern matching of these values:
https://github.com/ocaml/ocaml/blob/trunk/parsing/parsetree.mli#L145

What I would like to do is:

   | [Rtag the_whole_4_tuple] ->
       the_whole_4_tuple

However, when I try to do that, I am getting:

  Error: The constructor Rtag expects 4 argument(s),
         but is applied here to 1 argument(s)

This:

    | [Rtag (f1,f2,f3,f4)] ->
        f1,f2,f3,f4

of course works but (regardless of the chosen bound variable names), it looks amateurish.

What's the right way to do this?
(I would like just to bind a 4-tuple and then return it)

(Apologies in advance for a stupid question.)


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             reply	other threads:[~2017-10-19 13:38 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-10-19 13:38 Matej Košík [this message]
2017-10-19 14:16 ` vrotaru.md
2017-10-19 14:24   ` Matej Košík
2017-10-19 14:29     ` vrotaru.md
2017-10-19 14:30       ` Olivier Nicole
2017-10-19 14:31     ` Alan Schmitt
2017-10-19 14:34 ` Gabriel Scherer
2017-10-19 14:40   ` Matej Košík
2017-10-19 14:44   ` vrotaru.md

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