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From: mccaugh@uiucdcs.UUCP
Newsgroups: net.lang
Subject: Re: High-levelity
Message-ID: <26400021@uiucdcs.UUCP>
Date: Sat, 29-Dec-84 19:47:00 EST
Article-I.D.: uiucdcs.26400021
Posted: Sat Dec 29 19:47:00 1984
Date-Received: Thu, 3-Jan-85 00:55:32 EST
References: <83@mit-athena.UUCP>
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Nf-ID: #R:mit-athena:-8300:uiucdcs:26400021:000:1236
Nf-From: uiucdcs!mccaugh    Dec 29 18:47:00 1984


 Re: the question of hi-levelity--
     It seems to me that what eludes us in the way of definition is that we
     have yet to define "levelity" itself before we can assess the "hi-ness"
     of it...It was my understanding that Bell's classic on Computer Struct-
     ures might be a first resort to the problem: if by "level" we mean some
     "layer" of abstraction between programmer and bare machine,  then  per-
     haps the lowest-level languages are indeed the assembly languages  that
     are (except for macros) in 1-to-1 correspondence with the machine's own
     language. Alternatively, we might think of "hi-ness" of levels not only
     in terms of distance from the physical machine but (since they are lay-
     ers of "abstraction") also in terms of what virtual machine  does  play
     host to that language, e.g., the string-oriented machine that one might
     have in mind to interpret his Snobol program.  That is to say, "height"
     of the language level might pertain to the virtual machine instead  of
     the language, the usefulness of which concept is that then one can be-
     gin to think of equating languages level-wise if the virtual host  can
     interpret them both.


     uiucmsl!mccaugh