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From: faustus@yew.Berkeley.EDU (Wayne A. Christopher)
Newsgroups: comp.lang.lisp
Subject: Re: Are "destructive" functions really destructive?
Message-ID: <20197@pasteur.Berkeley.EDU>
Date: 2 Dec 89 00:55:15 GMT
Sender: news@pasteur.Berkeley.EDU
Reply-To: faustus@yew.Berkeley.EDU (Wayne A. Christopher)
Organization: University of California at Berkeley
Lines: 9

I think there are other reasons to use destructive operations besides
efficiency.  If you have a large and complex data structure, sometimes
you have to walk down a long path of pointers to get to the item you want,
and it's a lot easier to change it in place than to write a long string
of setf's to make sure everything points to the right place.  In a case
like that, if you can guarantee that you will never change the first item
of a list, you really want delete, et al to work "the right way".

	Wayne