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From: "Daniel Bünzli" <daniel.buenzli@erratique.ch>
To: "Milan Stanojević" <milanst@gmail.com>
Cc: Caml-list <caml-list@inria.fr>
Subject: Re: [Caml-list] GADT existential escape
Date: Thu, 19 Mar 2015 02:07:19 +0100	[thread overview]
Message-ID: <596DAEC11B474882835CEA10AAACE35E@erratique.ch> (raw)
In-Reply-To: <CAKR7PS_K5A5XR0nDnMv4z23LjxGBoi299vKY3+fccd1HuSEM-A@mail.gmail.com>

Le jeudi, 19 mars 2015 à 01:39, Milan Stanojević a écrit :
> Can you give some hypothetical example code ?
type 'a key = ?
type binding = B : 'a key * 'a -> binding
type dict = binding list  
let lookup : dict -> 'a key -> 'a option = fun d k -> ?

Is it possible to specify a `'a key` type that allows `lookup` (with the obvious semantics) to be written ? This is trivial to achieve with a universal type, see http://mlton.org/PropertyList

Best,

Daniel



  reply	other threads:[~2015-03-19  1:07 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-03-19  0:29 Daniel Bünzli
2015-03-19  0:39 ` Milan Stanojević
2015-03-19  1:07   ` Daniel Bünzli [this message]
2015-03-19  1:27     ` Milan Stanojević
2015-03-19 10:44       ` Daniel Bünzli
2015-03-19 11:02         ` Jeremy Yallop
2015-03-19 11:34           ` Daniel Bünzli
2015-03-19 13:22             ` Daniel Bünzli
2015-03-19 16:46             ` Milan Stanojević
2015-03-19 17:14               ` Daniel Bünzli
2015-03-19 17:15                 ` Frédéric Bour
2015-03-19 17:22                   ` Milan Stanojević
2015-03-19 17:41               ` Jeremy Yallop
2015-03-19 18:29                 ` Alain Frisch
2015-03-19 16:31           ` Milan Stanojević
2015-03-19 11:05         ` Jeremie Dimino
2015-03-19 11:34           ` Daniel Bünzli
2015-03-19 11:59             ` Jeremie Dimino
2015-03-20 13:50               ` Yaron Minsky

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