[R6RS] Document endgame

[dyb at cs.indiana.edu]

> - The chapters on syntax-case and libraries haven't been integrated
>   yet.  Kent, could you clarify what work you're still going to do on
>   them, and by when?  Could you help with the description of
>   `syntax-rules'?

The syntax-case text is in pretty good shape.  It needs to mention
declarations when it talks about body expansion, it needs to include
syntax-lambda, it needs to say something about the interaction with
libraries, it needs to talk about raising exceptions in a few more
places, and it needs to describe quasisyntax.  All of this should be
relatively easy.

BTW, Should the syntax text document syntax-violation?

The library text is not in such good shape.  There are some problems
already with the description of phasing, some but not all of which I have
tried to address, and we have to figure out how to account for the fact
that both the phased and unphased models are now acceptable.

Matthew, it would help if you could let me know how you think the library
text needs to be modified to reflect both options and also let me know
about any other changes you think need to be made to the text.  The
current document source is committed in srfi/library/library.stex,
complete with a grammar that is currently broken and several FIXMEs.

I'm going to try to update the syntax and library text by Sunday.  I'm
also concurrently working with Aziz Ghuloum on a combined syntax-case and
library reference implementation; I won't feel right about the text unless
we have actually implemented what it describes.

Kent