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From: Troy Hinckley <troyhinckley@gmail.com>
To: emacs-devel@gnu.org
Subject: question about Qnil representation
Date: Wed, 26 Oct 2022 09:40:30 -0600	[thread overview]
Message-ID: <5a00e93e-5f44-4865-aeeb-51f0aced9996@Spark> (raw)
In-Reply-To: <5a560265-fa81-42d2-945b-ab85d72df9e6@Spark>

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I have been reading through the C source to try and learn it and understand it better. I saw in Changeling.13 an entry From Paul Eggert on 2015-01-05 with “Use 0 for Qnil” As a fix for Bug#15880. How does this work in practice? It looks like symbols are just pointers, but 0 would not be a valid pointer. I don’t see any special code for handling the null case.

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       reply	other threads:[~2022-10-26 15:40 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <5a560265-fa81-42d2-945b-ab85d72df9e6@Spark>
2022-10-26 15:40 ` Troy Hinckley [this message]
2022-10-26 16:00   ` question about Qnil representation Eli Zaretskii
2022-10-26 16:04     ` Troy Hinckley
2022-10-26 16:09       ` Eli Zaretskii
2022-10-27  0:45       ` Po Lu
2022-10-26 16:16   ` Matt Armstrong
2022-10-26 16:22     ` Troy Hinckley
2022-10-26 16:45       ` Eli Zaretskii
2022-10-26 18:46         ` Troy Hinckley
2022-10-26 19:01           ` Stefan Monnier
2022-10-26 19:03           ` Eli Zaretskii
2022-10-27  0:47           ` Po Lu

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