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From: bobo@avogadro.arc.nasa.gov (Mark Friedman)
Subject: Re: PROPOSAL: packages
In-Reply-To: pertti@white.cs.rhbnc.ac.uk's message of 4 Nov 1994 17:46:12 GMT
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References: <1994Nov1.072410.21708@wisipc.weizmann.ac.il>
	<BAECHLER.94Nov1161424@liasun6.epfl.ch> <39ds14$qjr@sun.rhbnc.ac.uk>
Date: Wed, 9 Nov 1994 00:22:42 GMT

In article <39ds14$qjr@sun.rhbnc.ac.uk> pertti@white.cs.rhbnc.ac.uk
(Pertti Kellomaki) writes:

   The lack of a good package system has been one of my main gripes in
   using Scheme in introductory programming. ... I know perfectly well
   that you can get the same effect by creating a closure and doing
   set!s to global variables from there, but this is not as clean as
   one would hope, and moreover it requires understanding closures.

If it's not required that they understand the implementation of
packages then just create a set of macros that implement a package
system (such as the the closure and assignments approach that you
mention) and present it to your students as a built in facility.

-Mark
-- 
Mark Friedman
NASA-Ames Research Center
MS 269-2
Moffett Field, CA 94035-1000

vmail: (415) 604-0573
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