SPARK

About SPARK

SPARK stands for the Scanning, Parsing, and Rewriting Kit. It formerly had no name, and was referred to as the "little language framework." The first version (circa 1998) was described in the paper Little Languages in Python at the 7th International Python Conference.

SPARK is written in 100% pure Python, and is made available as open source.

News

• 19 May 2009: I should clarify that. SPARK is in the Python distribution in the "Parser" source directory, not in the Python library. This means that you can't just import it directly, unfortunately.
• 26 June 2007: John DeGood pointed out that SPARK is in the Python distribution now – yay!
• 02 March 2006: added a link to Andrea Mocci's elcc project on SourceForge.
• 26 August 2002: David Mertz' Charming Python column looks at SPARK in this article.
• 14 May 2002: SPARK version 0.7 pre-alpha-7 is available. It fixes a scanner bug that manifested itself when a pattern matched zero characters (not an especially practical thing to do before pre-alpha-6 was released yesterday!).
• 13 May 2002: SPARK version 0.7 pre-alpha-6 is available, which adds a method to GenericScanner to get and set the scanner's position.
• 16 February 2002: SPARK version 0.7 pre-alpha-5 is available. This version should work properly with Python 2.2.
• 26 November 2001: A Japanese translation of the IPC7 paper is available, thanks to Yasuhiro Osawa.
• 01 November 2001: SPARK version 0.7 pre-alpha-4 is available for testing. This version fixes a bug which could arise under an obscure set of circumstances.
• 19 September 2001: it looks like Python's garbage collector can really kill off the performance of 0.7pre3; brilliant solutions are, as always, welcome!
• 14 September 2001: another alpha pre-release, version 0.7 pre-alpha-3, is available for testing.
• 29 August 2001: an alpha pre-release, version 0.7 pre-alpha-2, is available for testing. (Finally!)
• 27 April 2000: Version 0.6.1 released, to fix a bug in GenericParser.
• 13 April 2000: Version 0.6 released. Mostly bug fixes, and parser performance improvements.
• 02 February 2000: some new features (including speed enhancements) are coming in the next major version, but they fall under the heading of "research" so I won't commit myself to a release date yet. Problems reported in the current release:
  • I broke the ordering guarantee when doing reflection, which should only affect you if you're subclassing scanners. Thanks to Gordon McMillian and Richard White for pointing this out.
  • Nicky Sandhu reports that a slight modification is required to get things working with JPython. I will verify this before the next release.
  If the next major release is delayed I may issue a minor release to fix these problems and get some of the less-radical changes distributed.
• 20 October 1999: Version 0.5 released. Major changes include scanner speedups and a proper ambiguity-resolution mechanism. (I haven't included the VHDL example since it needs some changes to work with the latest version, sorry!)
• 20 August 1999: Coming attractions in the next release, which I expect to be late September-October, will include:
  • Some new examples, including a contributed VHDL parser from Jan Decaluwe.
  • Enhancements and speedups to the scanner class, thanks to Tim Peters.
  • The reflection mechanism used by GenericScanner and GenericParser will follow the usual inheritance rules, so t_ and p_ methods can be overridden properly.
• 11 May 1999: Version 0.4 released. New classes for automagic tree building and tree pattern matching.
• 15 March 1999: a PDF version of my paper is available, thanks to Darrell Gallion.
• 04 February 1999: Version 0.3 released.
• 29 January 1999: Much to my surprise, empty rules seem to work properly -- sorry for any inconvenience this may have caused. Also, the next release (next week?) will include a parser for Python.
• 19 January 1999: Version 0.2 released.

Documentation

• The IPC7 paper describes the early version of SPARK.
  • PDF
  • HTML
• The release notes document changes and enhancements, as well as hints and caveats.

Download

• The latest version (0.6.1). Please note: this version has not been updated for some time; I strongly recommend you use SPARK version 0.7 pre-alpha-7 instead. Despite the "pre-alpha" status, it's been used for years successfully.

Problems uncompressing? Some people have downloaded one of the .gz files above, only to have it be un-unzippable. Seems that some browsers do you the favor of automagically uncompressing the file for you, but neglect to rename it! So if GNU Zip complains about the file, check to see if it's already uncompressed.

Projects Using SPARK

• Python compiler (SPARK's bundled in Python 2.5.1)
• Pygoo
• Elcc
• Lython
• MOSDEF
• Crystal
• Decompyle
• Grouch
• Möbius Python
• Parrot
• PyFort
• PyRAF
• VHDL parsing
• Showgrammar
• SelectOracle

Contributors

People who have helped me out by sending suggestions, patches, and/or large sums of money in small unmarked bills:

• Jan Decaluwe
• Paul Dubois
• Mike Fletcher
• Darrell Gallion
• Kevin Jacobs
• Nick Mathewson
• David Mertz
• Gordon McMillan
• Amit J. Patel
• Tim Peters
• François Pinard
• Eric S. Raymond
• Dickon Reed
• Nicky Sandhu
• Richard White

Early work on SPARK was supported in part by development of Guide.

Legalese

• SPARK
• SPARK
• SPARK
• SPARK
• SPARC (For Heaven's sake, this one isn't even spelled the same way! If someone can't tell the difference, they probably shouldn't be doing anything as exacting as writing software.)