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From: misha@gracilis.ai.mit.edu (Mike Bolotski)
Newsgroups: comp.lang.misc
Subject: Re: Technical: Definitions of ``Poynter'', ``Shyfting''
Message-ID: <11925@life.ai.mit.edu>
Date: 16 Nov 90 16:34:03 GMT
References: <19485:Nov1608:33:4490@kramden.acf.nyu.edu>
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Organization: MIT Artificial Intelligence Laboratory
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In article <19485:Nov1608:33:4490@kramden.acf.nyu.edu> brnstnd@kramden.acf.nyu.edu (Dan Bernstein) writes:
>Please include technical content, and only technical content, in any
>followup to an article whose subject begins with ``Technical:''. Change

Sounds good to me.

>Poynter: An object that can hold the address of another object (perhaps
>of a restricted type). As usual, a poynter supports assignment and
>comparison. It may be set to the ``address of'' an object. It may be
>``dereferenced'' in order to evaluate or modify the object whose address
>it holds. These operations are explicit.

There is also a beastie called "reference", which supports assignment
and dereference, but *not* comparison. It's used in ML and 
FX-90 (a locally developed language). I believe the C++ refs also
do not support comparison. Similarly, arithmetic on references
is not supported.

>Shyfting: The operation of re-indexing a reference to an array with a
>different base, so as to produce a reference to the same object with the
>new indices.

What is the working definition  of "reference" in the above?

Mike Bolotski          Artificial Intelligence Laboratory, MIT
misha@ai.mit.edu       Cambridge, MA