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Re: [Caml-list] Subtyping structurally-equivalent records, or something like it?

Dario Teixeira
- Sylvain Le Gall
  - AUGER Cédric
  - Sylvain Le Gall
    - rossberg@m...
      - Sylvain Le Gall
        
        Fabrice Le Fessant
      - Goswin von Brederlow
        
        rossberg@m...
        
        Goswin von Brederlow
    - Edgar Friendly
      - Goswin von Brederlow
      - Yaron Minsky

Date:	-- (:)
From:	Sylvain Le Gall <sylvain@l...>
Subject:	Re: Subtyping structurally-equivalent records, or something like it?

On 01-05-2010, Dario Teixeira <darioteixeira@yahoo.com> wrote:
> Hi,
>
>>  type kinematic = { lin: Vec.t; ang: Vec.t }
>>
>> Which I've been using to represent a medley of physical attributes (force, > momentum, velocity, etc.).
>
> I second StÃ©phane's suggestion of using phantom types; moreover,
> I recommend you read an article that discusses them to some detail
> and covers their use for precisely this sort of problem:
> http://camltastic.blogspot.com/2008/05/phantom-types.html
>

I really like the use of private type abbreviation for phantom type:
http://ocaml.janestreet.com/?q=node/77

Regards,
Sylvain Le Gall