Version française
Home     About     Download     Resources     Contact us    
Browse thread
The option -rectypes
[ Home ] [ Index: by date | by threads ]
[ Search: ]

[ Message by date: previous | next ] [ Message in thread: previous | next ] [ Thread: previous | next ]
Date: -- (:)
From: Jerome Vouillon <Jerome.Vouillon@i...>
Subject: Re: The option -rectypes
On Wed, Nov 24, 1999 at 01:59:36AM +0100, Gerd Stolpmann wrote:
> I have some code that compiled in 2.02, but in 2.03 I need the new option
> -rectypes of the compilers.

This is a bug in the occur check. It will be corrected in the next
release.

> - I have thought about the type 'a node extension as 'a. If I apply the
>   constraint of "node", the condition must hold that 
>       ('a node extension as 'a) node extension 
>   unifies with
>       ('a node extension as 'a) node #extension
>   Normally, a closed class type does not unify with an open class type,
>   and I wonder why this is accepted at all.

The type of self cannot be unified with closed object type: this would
prevent a further extension of the class.  But a type such as
#extension can be unified with a closed object type.  In particular,
it can always be unified with the same type without "#".

-- Jérôme