"trigrat" caught in infinite loop - depending on how you call it

I read your preceding answer a bit too fast :o)

For circular structures, maybe this would help:
http://rosettacode.org/wiki/Deepcopy#Common_Lisp


Le 07/11/2012 19:35, Stavros Macrakis a ?crit :
> Well, it looks as though it's not an issue in the assume database, 
> anyway....  All we need to do is wrap $trigrat with (let ((varlist)) 
> ...).
>
> As for comparing circular lists, yes of course you can write code to 
> do the comparison, avoiding infinite recursion.  But it's more subtle 
> than eq or equal.
>
>    -s
>
> On Wed, Nov 7, 2012 at 1:22 PM, Jean-Claude Arbaut 
> <jeanclaudearbaut at orange.fr <mailto:jeanclaudearbaut at orange.fr>> wrote:
>
>     You're right, of course, but isn't there a way to check changes in
>     assume database ?
>     I didn't look its type in maxima sources, but it must be a lisp
>     object anyway.
>
>     Le 07/11/2012 18:38, Stavros Macrakis a ?crit :
>>     State is stored in more places than just symbols' values.  One
>>     possibility is something in the 'assume' database (which is
>>     stored in symbols' plists and is a circular list structure that
>>     gets modified in-place, so neither equal nor eq are good ways of
>>     comparing two versions....
>>
>>           -s
>>
>>
>
>
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