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From: milor001@maroon.tc.umn.edu (R A Milowski)
Subject: Re: Parsing utilities in Scheme
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References: <D080yL.In1@news.cis.umn.edu> <FOX.94Dec5134439@first.cs.nyu.edu>
Date: Wed, 7 Dec 1994 18:38:43 GMT
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In article <FOX.94Dec5134439@first.cs.nyu.edu>,
David Fox <fox@graphics.cs.nyu.edu> wrote:
>In article <D080yL.In1@news.cis.umn.edu> milor001@maroon.tc.umn.edu (R A Milowski) writes:
>
>] I am looking for parsing utilites for building "dynamic" parsers in Scheme.
>
>I have a file in my archives called "lalr.scm", by Mark Johnson,
>mj@cs.brown.edu, that should do what you want.  Don't know where I
>got it, and I haven't ever used it.  Let me know if you're
>interested.

Well, I have that.  I have basically picked up every parsing utility I could
find but they don't seem to provide what I need.  Being new to Scheme I could
be wrong!  ;)

I need parsing tools that allow me to re-define the tokens that the lexical
analyzer produces.  Essentially, I am trying to parse SGML and SGML allows
the delimiters of SGML to be re-defined.  Thus, the basic expressions that the
parser is based on has to be re-defined mid-parse.  I could write a special
lexical analyser to do this (and I have done this in C++) but I don't think I
should have to.

I picked up the bigloo system which has lex/yacc counter parts for Scheme but
it seems that it does allow "un-bound" expressions because I tried to build
the grammar at un-time.  Again, I may have been doing it wrong since I am
not a Scheme expert!


==============================================================================

R. Alexander Milowski
SGML Operations Manager        milor001@maroon.tc.umn.edu
Microcom Inc.                  (612) 825 - 4132
"An SGML Solutions Company"

==============================================================================


