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Attach an invariant to a type

Dawid Toton
- Romain Bardou
  - David Teller
    - Romain Bardou
      - Hezekiah M. Carty
        
        Stéphane_Lescuyer
        
        StÃ©phane Glondu
        
        Dawid Toton
        
        Edgar Friendly
        
        Keiko Nakata
        
        Romain Bardou

Date:	-- (:)
From:	Dawid Toton <d0@w...>
Subject:	Re: [Caml-list] Attach an invariant to a type

> I guess that making types like "int" private would require the system
> (among other things) to decide whether you're using a given integer as
> a Subindex.t or not.

Suppose we have "type t = private int" in module Subindex.

Is the following construct legal: let (a:Subindex.t) = 2 ?
It shouldn't be - to prevent me from constructing values of this type. 
So I couldn't "use given integer as Subinddex.t".