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Message-ID: <52B88E12.20002@hot.ee>
Date: Mon, 23 Dec 2013 21:25:06 +0200
From: Misha Aizatulin <avatar@hot.ee>
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Subject: [Caml-list] Pattern match fall-through for GADTs

hi all,

  I decided to give GADTs a go and realized that I don't know how to
make pattern matches fall through in a familiar fashion. The code [1]
below gets accepted but [2] does not. Is there anything I can do to
avoid spelling out the same case several times?

Best,
  Misha

[1]
type 'a t =
| I1 : int t
| I2 : int t
| B1 : bool t
| B2 : bool t

let f (type a) (t : a t) =
  match t with
  | I1 -> 0
  | I2 -> 0
  | B1 -> 1
  | B2 -> 1

[2]
let f (type a) (t : a t) =
  match t with
  | I1
  | I2 -> 0
  | B1
  | B2 -> 1