[XPS-devel] Recent Changes & Update

[Reid S. <re...@re...>]

Everyone,

My recent set of changes have led to the first executable program for
the XPS: an early version of the compiler, xplc. This current version
uses Xerces to parse an XPL program and check it for syntax/grammar
validity. I'm currently working on extending this to (a) capture the
symbol table and (b) validate the compilation. Once all that is done,
I'll turn my attention to the back end and start generating executable
code from XPL source. 

If you want to try out the parser and try writing programs in XPL,
here's what I suggest you do:

1. Get the latest tarball from SourceForge
(http://sourceforge.net/projects/extprosys)
2. Get Xerces-C 2.2 (i.e. the "developer snapshot pre-release of 2.2",
at http://xml.apache.org/xerces-c/)
3. Get ICU 2.2 from IBM (http://oss.software.ibm.com/icu/
4. Configure & build both Xerces-C and ICU into a common install
directory
5. Configure & build XPL (use the bootstraph.sh script at the top level
directory)
6. Make sure you source the <xpl>/config/bashrc file in your bash shell
(you might need to configure it first).

The modules you need are: util, test, mem and xplc.

Once xplc is finished build, it should produce a program named xplc
which you can use to parse your
XPL programs. Just provide it with a file name to parse.

If you'd like to try the above, please let me know as I'm quite
interested in having someone else verify the build and configuration of
XPL.  The above should work on RedHat 7.2 or later. It should also work
on other recent 
GNU/Linux systems and possibly on cygwin under Windows 2K.

If there are any questions, please ask. I'll help you.

Other changes:
1. Schema updates (<xpl>/src/schemas/XPL.xsd). The language is MUCH
simpler now. I got rid of the abstract
   schema components and reduced the operator complexity by 130 element
types while adding more functionality
2. HelloWorld.xpl (<xpl>/src/schemas/tests/HelloWorld.xpl). This is an
XPL program to print "Hello World." but it
   does it in 5 languages and uses method discriminants. Its a bit of an
"overkill" for the traditional HelloWorld 
   program but its instructional.
3. The memory system is up and running. I've tested it heavily and works
well. 
4. Lots of cleanup in makefiles and configuration stuff.

Happy XPLing.

Reid.

P.S. If you write any XPL programs, please let me know. I'd like you to
include them in the test suite for the compiler.