🚀 go-pugleaf

Bellcore has given approval for me to release into the public domain
some common-lisp code for a bottom-up Relational Language parser.  A
tar file is available through anonymous ftp from host
flash.bellcore.com in the directory rl. If there are any mac users out
there who would like me to create a mac compressed file, let me know.
Feel free to pass on the info to whoever you think might be
interested.  I only ask to be kept informed, if possible, about who is
using it.

>From the README file:


The RL files contain code for defining Relational Grammars and using
them in a bottom-up parser to recognize and/or parse expressions in
Relational Languages.  The approach is a simplification of that
described in Wittenburg, Weitzman, and Talley (1991),
Unification-Based Grammars and Tabular Parsing for Graphical
Languages, Journal of Visual Languages and Computing 2:347-370.
Reprints are available at this writing from kentw@bellcore.com.

The code is written in Common Lisp, and has been tested for Allegro
Common Lisp 4.1 on SGIs, Allegro Common Lisp 4.1 on Suns, and
Macintosh Common Lisp 2.0 on Macs.  

This code is designed to support the definition and parsing of
Relational Languages, which are characterized as sets of objects
standing in user-defined relations.  Correctness and completeness is
independent of the order in which the input is given to the parser.
Data to be parsed can be in many forms as long as an interface is
supported for queries and predicates for the relations used in grammar
productions.  To date, this software has been used to parse recursive
pen-based input such as math expressions and flowcharts; to check for
data integrity and design conformance in databases; to automatically
generate constraints in drag-and-drop style graphical interfaces; and
to generate graphical displays by parsing relational data and
generating output code.


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Kent Wittenburg
Computer Graphics and Interactive Media Group
Bell Communications Research, MRE 2A-347 
445 South St. 
Morristown, NJ 07962-1910 
email: kentw@bellcore.com