🚀 go-pugleaf

On 8 Nov 90 17:40:42 GMT, anw@maths.nott.ac.uk (Dr A. N. Walker) said:

anw> Furthermore, if I am denied access to the algebra of locations,
anw> then some useful ideas like anonymous objects, and like remembering
anw> locations, become inexpressible.

pcg> They are most definitely not useful at the application level,

anw> They most definitely are!  When I give people directions to my
anw> house, I include things like: "Take the third on the right, ...",
anw> "If you get to the Hemlock Stone, you've gone too far, you should
anw> ...", and "If you get lost, ask for Priory Island, and try again
anw> from there".

This is an *implementation*.

I think we have very different ideas on what is application design and
what is implementation design, and in particular between data design and
representation design. More precisely, IMNHO you don't make much
distinction between the two aspects. Unfortunately.

Just to restate my position, while we are talking past each other: when
doing data design pointers are extraneous and therefore unwelcome
details (and so Chris Holt is right). When doing representation design
they are an invaluable technology (and so you are right too).

For application oriented languages (SQL, Hermes) pointers are
questionable; for implementation oriented languages (C, Algol 68)
pointers are important (and Andy Lowry is somehow right on both
accounts too).
--
Piercarlo Grandi                   | ARPA: pcg%uk.ac.aber.cs@nsfnet-relay.ac.uk
Dept of CS, UCW Aberystwyth        | UUCP: ...!mcsun!ukc!aber-cs!pcg
Penglais, Aberystwyth SY23 3BZ, UK | INET: pcg@cs.aber.ac.uk