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From: Stefan Monnier <monnier@iro.umontreal.ca>
To: emacs-devel@gnu.org
Subject: map-char-table, optimize-char-table and `equal' comparisons
Date: Sat, 10 May 2008 16:21:27 -0400	[thread overview]
Message-ID: <jwvej89rjzy.fsf-monnier+emacs@gnu.org> (raw)


Both map-char-table and optimize-char-table compare consecutive values
using `equal' to determine whether to merge them into ranges.

I can see that it may sometimes be useful, but it is dangerous since it
may lose object identity information (obviously) and more importantly
because `equal' can fail when comparing cyclic objects.

I happened to be manipulating char-tables that map chars to other
char-tables, sometimes in cyclic ways and that makes it impossible to
use map-char-table ;-(

Any objection to changing the internal comparison predicate to `eq'?


        Stefan




             reply	other threads:[~2008-05-10 20:21 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-05-10 20:21 Stefan Monnier [this message]
2008-05-14  7:59 ` map-char-table, optimize-char-table and `equal' comparisons Kenichi Handa
2008-05-16  4:48   ` Stefan Monnier
2008-05-16  5:43     ` Kenichi Handa

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