From: Daniel Colascione <daniel@censorshipresearch.org>
To: Emacs development discussions <emacs-devel@gnu.org>
Subject: Why isn't the string returned by symbol-name read-only?
Date: Sat, 23 Jan 2010 15:55:44 -0500 [thread overview]
Message-ID: <4B5B6250.1080108@censorshipresearch.org> (raw)
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Consider
(let ((name (symbol-name 'foo)))
(aset name 0 ?x)
(cons name (symbol-name 'foo)))
That yields ("xoo" . " xoo")
Now try
(let ((name (symbol-name 'car)))
(aset name 0 ?x)
(cons name (symbol-name 'car)))
That returns in an error when you try to evaluate it. The object
returned by (symbol-name 'car) must have some read-only bit set.
Why isn't that bit set for *all* symbol names?
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next reply other threads:[~2010-01-23 20:55 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-01-23 20:55 Daniel Colascione [this message]
2010-01-23 21:53 ` Why isn't the string returned by symbol-name read-only? Chong Yidong
2010-01-24 0:33 ` alin.s
2010-01-24 9:48 ` Thien-Thi Nguyen
2010-01-24 1:12 ` Davis Herring
2010-01-24 11:19 ` alin.s
2010-01-25 3:08 ` Stefan Monnier
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