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From: gjr@hplgr2.hpl.hp.com (Guillermo (Bill) J. Rozas)
Subject: Re: expressiveness and strong type system?
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In-Reply-To: blume@zayin.cs.princeton.edu's message of 24 Mar 1996 00:54:42 GMT
Date: Mon, 25 Mar 1996 17:35:42 GMT
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In article <BLUME.96Mar23195442@zayin.cs.princeton.edu> blume@zayin.cs.princeton.edu (Matthias Blume) writes:

|   Abstract over the type of those `positions' in your data structure,
|   and then instantiate it with the appropriate sum type.  I grant you
|   that this sum type won't be constant throughout development, but at
|   each given iteration of the development/maintenance cycle it is a sum
|   of a finite set of types.

Really?  So what happens when I'm writing an object dumper/loader
library that any other program can use?

I would like to be done with it in finite time, and not have to add to
it every time someone invents a new type.

What about writing the garbage collector in the language itself (you
only need a handful of additional primitives)?  Etc.

There are many components of the runtime library that will have to
deal with future types.  I don't expect each user to have to rebuild
the library and integrate their code into it.
