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To: caml-list@inria.fr
Subject: type abbreviation for open polymorhic variants?
Message-Id: <20050818210343.D8E391EB0C3@labrador.eecs.harvard.edu>
Date: Thu, 18 Aug 2005 17:03:43 -0400 (EDT)
From: nr@eecs.harvard.edu (Norman Ramsey)
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	version=3.0.3

I wish to define an abbreviation for the following type:

         [> `Nil
    	 | `Number   of float
    	 | `String   of string
    	 | `Function of func
     	 | `Table    of table
         ]

I am assuming that the underlying machinery involves something like
row polymorphism, but I don't know how to name the 'row variable'.
I tried

  type 'a t = ['a 
              | `Nil
              | `Number   of float
              | `String   of string
              | `Function of func
              | `Table    of table
              ]

but this suggestion was roundly rejected by the compiler.

Does anybody know how to do this?  I couldn't find anything in the
syntax for polymorphic-variant type expressions.


Norman