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Why isn't -rectypes command line option the default
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Date: -- (:)
From: Ville-Pertti Keinonen <will@e...>
Subject: Re: [Caml-list] Re: Why isn't -rectypes command line option the default

On Mar 21, 2007, at 4:13 AM, Erik de Castro Lopo wrote:

> Wouldn't it be nicer to be able to specify the rectypes behaviour
> per type? Maybe something like this would work:
>
> 	rec type 'a t = 'a * 'a t Lazy.t

It would probably be possible to allow that by default with no extra  
keyword, since errors are unlikely when writing a type explicitly.

But the ability to write recursive type aliases would not make  
actually creating recursively typed values all that convenient, you'd  
have to give the type explicitly (I'd rather just use a variant and a  
constructor).

Note that in the example using -rectypes posted by Zheng Li, the type  
'a t is never actually used for anything - presumably it's intended  
as an illustration to the reader, and could just as well be a comment  
-  the type inferred for fib is compatible, but not named int t.