Path: news.eternal-september.org!eternal-september.org!.POSTED!not-for-mail
From: "B. Pym" <Nobody447095@here-nor-there.org>
Newsgroups: comp.lang.lisp
Subject: Re: I still don't get MAPCAN
Date: Thu, 26 Jun 2025 23:32:38 -0000 (UTC)
Organization: A noiseless patient Spider
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B. Pym wrote:

> (mapcan (lambda (e) (if (interestingp e) (list e) nil)) huge-list))

Shorter:

(mapcan (lambda (e) (and (interestingp e) (list e))) huge-list))