Re: [Sbcl-help] Problem with the MOP

[Pascal C. <cos...@we...>]

On 3 Jul 2004, at 1:56, Pascal Costanza wrote:

> OK, I have hacked around a bit, and I think I can provide a better 
> question. In fact, I think I have detected a bug. Here is the code:
>
> (defmethod compute-discriminating-function
>            ((gf special-generic-function))
>   (let ((dfun (call-next-method))
> 	(dynamic-scope-prototype (class-prototype (dynamic-scope gf))))
>     (lambda (&rest args)
>       (declare (dynamic-extent args))
>       (apply dfun dynamic-scope-prototype args))))
>
> I have checked the MOP specs, and this should work. (The MOP 
> explicitly states that one can override 
> compute-discriminating-function, which includes modifying the return 
> value of call-next-method.)

In the meantime, I have browsed through the HyperSpec and have found 
some sections that indicate that a Common Lisp implementation is 
allowed to reject generic function calls that provide less arguments 
than the function's lambda list expects. Since there exist good reasons 
why one would want this, I can't follow that approach anymore. Luckily 
I have found another way to achieve what I want yesterday, and I am 
pretty sure that it is more portable than my previous solution. 
Hopefully, this means that I will be able to release a new version of 
AspectL that runs on a considerable number of implementations soon.


Pascal

--
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Jack: "Great."
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