"guarded" fetch from hashed array



Thanks for geting back to me.

On Wed, Feb 08, 2012 at 02:10:14PM -0500, Stavros Macrakis wrote:

> The "hash_table" style is problematic in various ways and I would recommend
> it be rethought and replaced.

I would favor this. As a newcomer to maxima, I find these hashtables
confusing. I guess I was looking for something like a Python
dictionary...

> In the meantime, though, you can define the following:
> 
> :lisp (defun $hash_table_defined (ar i) (multiple-value-bind (val ok)
> (marrayref-gensub ar i nil) ok))

I'll give it a go.

Do you plan to implement something like this for real in maxima?

-- 
Best Regards
Edd Barrett

http://www.theunixzoo.co.uk