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Re: plist-put modification by side effect


From: Andreas Politz
Subject: Re: plist-put modification by side effect
Date: Mon, 02 Feb 2009 19:07:18 +0100
User-agent: Mozilla-Thunderbird 2.0.0.17 (X11/20081018)

Thien-Thi Nguyen wrote:
() Dan Davison <address@hidden>
() Sun, 1 Feb 2009 11:23:14 -0500

   So if I've understood this then I think the docstring is inaccurate
   since `The PLIST is modified by side effects.' is not necessarily
   true.

When something is consed onto the head of a list, the list is not modified.

thi



I believe the whole term 'side effect' is a lisp heritage, where it marks a
destructive function, one which _may_ modify it's arguments.
In constrast to 'functional functions' like append etc. So the emphasis is
on 'altering it's argument' and not on 'dont' bother with the return value'.

-ap


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