Re: Question about loop

Jeff Barnett wrote:
Does the Common Lisp spec say anything about whether the following is well defined given that the elements of "list" are unique:

(loop for x in list
when (p x)
do (setq list (delete x list)))

See http://www.lispworks.com/documentation/HyperSpec/Body/03_f.htm

But I wouldn't worry too much and just switch to a non-destructive version:

(loop for x in list
unless (p x) collect x into new-list
finally (setq list new-list))


Pascal

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