Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!apple!bbn!gateway!DINO.BBN.COM!kanderso
From: kanderso@DINO.BBN.COM
Newsgroups: comp.emacs
Subject: Re: apply, mapcar, lack of setenv
Message-ID: <40832@bbn.COM>
Date: 2 Jun 89 15:24:19 GMT
References: <CSUWN.89Jun2041413@orchid.warwick.ac.uk>
Sender: news@bbn.COM
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In most lisps you can't apply things like 'or or 'and because the are special
forms, not functions.  Here is a recursive function that may do what
you want.  you could also use while.

(defun setenv (name new environment)
  (if (null environment) environment
      (if (= (string-match (format "%s=" name) (car environment)) 0)
	  (cons (format "%s=%s" name new) (cdr environment))
	  (cons (car environment) (setenv name new (cdr environment))))))