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From: Michael Heerdegen <michael_heerdegen@web.de>
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Subject: Re: display-buffer-alist actions
Date: Wed, 24 Feb 2021 21:57:55 +0100
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Joost Kremers <joostkremers@fastmail.fm> writes:

> IIUC no, the actions (the conses you mention) don't have conditionals.

But they are allowed to fail (i.e., return nil).  AFAIK actions are
tried in order until one succeeds.  So one could use special action
functions (e.g. trivial wrappers around the given actions that just fail
if a condition is not met) to get a conditional behavior inside the
`display-buffer' mechanism.

Michael.