Re: R5RS ratification [resend]

[Richard Kelsey <kelsey@research.nj.nec.com>]

   Date: Mon, 12 May 1997 11:41:58 -0400 (EDT)
   From: Aubrey Jaffer <jaffer@martigny.ai.mit.edu>

   On page 3 of the report, it says:

     some features are marked as library.  These can be easily
     implemented in terms of the other, primitive, features.  They are
     redundant in the strict sense of the word, but they capture common
     patterns of usage, and are therefore provided as convenient
     abbreviations.

   The procedure LIST is marked as a library procedure.  All the
   procedures I can think of which might generate NULL are marked as
   library procedures.  At least one procedure capable of generating ()
   should be non-library.

I don't understand why.  The empty list is available as '().

[Or you could define LIST as (LAMBDA ARGS ARGS) and use (LIST)
 to get the empty list.]

   Dynamic-wind should be a library procedure.  SLIB implements it using
   less than 30 lines of R4RS Scheme.

Yes, but to do so SLIB has to redefine CALL-WITH-CURRENT-CONTINUATION,
which doesn't really fit the notion of a `library' procedure.  Also,
getting those 30 lines of code right is nontrivial.

   I could check the report more throughly if I didn't have to grep
   through postscript (or paper) in order to find occurences of words.
   TeX source would be much easier to read.

True.  I am always reluctant to release the sources for a draft
document, but I'll package the Tex sources and make them available
when I get a chance.
                                      -Richard