Subject: Re: pedagogy question: introduce lists or pairs first?
From: rpw3@rigden.engr.sgi.com (Rob Warnock)
Date: 19 Mar 2001 05:08:34 GMT
Newsgroups: comp.lang.scheme
Message-ID: <99448i$1ed6v$1@fido.engr.sgi.com>
Shriram Krishnamurthi <sk+10@cs.brown.edu> wrote:
+---------------
| Max Hailperin <max@max.mcs.gac.edu> writes:
| > Sub-languages?  So structures are a feature of Scheme?  Which section
| > of the R5RS describes them? ;-) -max
| 
| Doesn't the Tenth Amendment in the Bill of Rights read
|   The powers not delegated in the Revised^N Report on the Algorithmic
|   Language Scheme, nor prohibited by it to the implementations, are
|   reserved to the implementations respectively, or to the users.
+---------------

Actually, R5RS itself reads:

	1.3.1 Primitive, library, and optional features
	...
	Implementations are free to omit optional features of Scheme or
	to add extensions, provided the extensions are not in conflict
	with the language reported here.

and AFAICT, structures[*] are not in conflict with the R5RS language.


-Rob

[*] As well as most of the other goodies in PLT Scheme: boxes, hash
    tables, classes/objects, threads, semaphores, sockets, the exception
    system, regexps, etc, etc.

    [Though multiple global namespaces *might* be outside the pale...]

-----
Rob Warnock, 31-2-510		rpw3@sgi.com
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