************************************************************
*                             Installation
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The Zebu runtime system is all you need if you want to use the
parser/generator that was produced by the compiler (in form of a .tab
file).

The Zebu-compiler is necessary in order to convert the external
grammar description (in form of a .zb file) into a LALR(1) parsing
table (in form of a .tab file), and associated printers and semantic
functions (in form of a <grammar-name>-domain.lisp file).

Installation
------------

1. Check whether the pathname for the Zebu directory is correct in your
installation.

2. In MCL evaluate

	(load "COMPILE-ZEBU.lisp")

This compiles all of ZEBU.

3. To use ZEBU evaluate

	(load "ZEBU-init.lisp")

	(zb:zebu)                ; to load the runtime system

	(zb:zebu-compiler)       ; to load the grammar compiler

	(zb:zebu-rr)             ; to load the rewrite-rule module



Alternative Installation (using DEFSYSTEM)
------------------------------------------

DEFSYSTEM makes it easier to load and compile grammars, since one does
not need to remember the location of a module in a directory
structure.  The bad news is that this DEFSYSTEM is incompatible with
the one maintained at CMU.  At some point we will clean this up.
(Anyone who would write the definition using the DEFSYSTEM distributed
by Mark Kantrovitz CMU should send me the file and I will include it in
the next version)
 
To install, follow the directions in ZEBU-sys.lisp.  You will need the
portable DEFSYS which is available at:
 http://www.cs.cmu.edu/afs/cs/project/ai-repository/ai/lang/lisp/code/tools/defsys/laubsch/

The most recent version defsys-5.7 can can be found on ftp.digitool.com 
in /pub/mcl/contrib as defsys-5.7.tar.gz.

The file ZEBU-sys.lisp defines three systems

	Zebu		        the runtime system
	Zebu-compiler	        the compiler
	Zebu-RR                 the rewrite rule system