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From: markf@zurich.ai.mit.edu (Mark Friedman)
Newsgroups: comp.lang.scheme
Subject: Re: Making programs out of modules in Scheme
Message-ID: <MARKF.91Jun19104522@montreux.ai.mit.edu>
Date: 19 Jun 91 14:45:22 GMT
References: <6384@goanna.cs.rmit.oz.au>
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Organization: M.I.T. Artificial Intelligence Lab.
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In-reply-to: ok@goanna.cs.rmit.oz.au's message of 19 Jun 91 07:11:20 GMT

In article <6384@goanna.cs.rmit.oz.au> ok@goanna.cs.rmit.oz.au (Richard A. O'Keefe) writes:

   I just received E-mail from someone who believes that Scheme as it
   currently stands does not have the facilities required to build a
   library out of modules.

   I claim that he is wrong, that Scheme as it stands provides
   everything we need to build programs out of modules that do not
   interfere with each other's name space.
   ...
       (library 'register ModuleName:symbol FileString:string)
       ...
       (library 'define ModuleName:symbol ExportName:symbol Value:any)
       ...
       (library 'require ModuleName:symbol)
       ...
       (library 'value Modulename:symbol ExportName:symbol)
   ...

   The implementation of (library mod . rest) is so trivial that it is
   left as an exercise for the reader.

Without LOAD it is not so trivial. LOAD is not in IEEE standard Scheme
(at least not in my draft).

   This suffices to show that the LANGUAGE permits the construction of
   modular libraries.

Certainly the language permits it. The question is whether the
standard language has sufficient capabilities to build a module
system.  Without LOAD or EVAL I don't see how to do it.

-Mark
--

Mark Friedman
MIT Artificial Intelligence Lab
545 Technology Sq.
Cambridge, Ma. 02139

markf@zurich.ai.mit.edu