Subject: Re: Smug scheme weenies?
From: (Rob Warnock)
Date: Sun, 16 Jan 2005 05:27:38 -0600
Newsgroups: comp.lang.lisp
Message-ID: <>
Ron Garret  <> wrote:
| (Rob Warnock) wrote:
| > Sorry for the imprecision, that's really what I meant by "thread-safe",
| > that *nobody* [in the same or another thread] could rebind it while
| > the cached address was being used.
| I understood what you meant, but I don't see why such a stringent 
| requirement is needed.  It seems to me that one thread rebinding a 
| variable should have no affect on the cached value in a different thread.

Sorry, you're right. What I said was sufficient for safety, but not
minimal (strictly necessary).

Back to our common point: Even given adequate attention to safety,
a special variable may be accessed many times with only one double-
indirection, so that the per-thread glovar/dynvar table approach
doesn't have to be expensive. 


Rob Warnock			<>
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