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[Caml-list] Constructors as functions and tuples in constructors
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Date: -- (:)
From: Dan Grossman <djg@c...>
Subject: Re: [Caml-list] Constructors as functions and tuples in constructors

Serge wrote:
> First, it would be nice to have constructors as functions like below:
> 
> List. map Some [17]

Leads to strange error messages and is trivially circumventable (replace 
Some with fun x -> Some x)

> Second, it would also be nice not to have "the concept of constructor
> arity", and treat the code below as correct:
> 
> type t = A of int * int
> let _ = 
>   match A (17, 0) with
>     A z -> match z with (x, y) -> ()

Works with type t = A of (int * int).  You put the parens in.  So the 
choice is yours.  The advantage of leaving them out is usually performance.

Others can give the long version of these answers...

--Dan



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