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From: peterr@utcsrgv.UUCP (Peter Rowley)
Newsgroups: net.lang
Subject: static links vs. displays
Message-ID: <2501@utcsrgv.UUCP>
Date: Sun, 16-Oct-83 19:19:28 EDT
Article-I.D.: utcsrgv.2501
Posted: Sun Oct 16 19:19:28 1983
Date-Received: Sun, 16-Oct-83 19:57:26 EDT
Organization: CSRG, University of Toronto
Lines: 13

I've been teaching some second year CS students about block-structured
languages and covered static links vs. displays.  When two mechanisms
like this coexist, one expects to find a tradeoff between them, but I
am at a loss to explain the tradeoff (fortunately, the students didn't
ask!).  As far as I can tell, a display takes only slightly more space
(one address per lexical level (the static link in the activation record
is replaced by the old display entry that the invocation set)) and is
always faster.  So, what is the advantage to static links that I'm missing,
or why are they ever used?  Non-technical reasons are welcome.

peter rowley,  University of Toronto Department of C.S., Ontario Canada M5S 1A4
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