Hi everyone, I would like to implement a parser for a mini-language and would appreciate some pointers. The type of text I would like to parse is an extension of:
http://www.websequencediagrams.com/examples.html For those that don't want to go to the link, consider the following, *very* simplified, example: ======= programmer Guido programmer "Fredrik Lundh" as effbot programmer "Alex Martelli" as martellibot programmer "Tim Peters" as timbot note left of effbot: cutting sense of humor note over martellibot: Offers detailed note, explaining a problem, accompanied by culinary diversion to the delight of the reader note over timbot: programmer "clever" as fox timbot -> Guido: I give you doctest Guido --> timbot: Have you checked my time machine? ======= >From this, I would like to be able to extract ("programmer", "Guido") ("programmer as", "Fredrik Lundh", "effbot") ... ("note left of", "effbot", "cutting sense of humor") ("note over", "martellibot", "Offers...") ("note over", "timbot", 'programmer "clever" as fox') Some observations: 1. I want to use indentation to identify blocks. (the site I referred to uses "end note" which I don't want) 2. "keywords" (such as "programmer", "note over") can appear in text, and should not then be misidentified 3. I was thinking of using http://effbot.org/zone/simple-top-down-parsing.htm as a guide; however, it is not clear to me how it could be adapted to handle observations 1 and 2. (If it "easily" could, just a few pointers would be enough, and I'll start from there...) 4. I want to do this only using modules in the standard Python library, as I want to use this to learn about the basics of parsing. So, please don't *simply* suggest to use a third-party module, such as [1] plex, [2] yapps, [3] pyparsing The learning journey is more important for me than just having a canned solution to my (current) parsing problem. Cheers, André [1] http://www.cosc.canterbury.ac.nz/greg.ewing/python/Plex/ [2] http://theory.stanford.edu/~amitp/yapps/ [3] http://pyparsing.wikispaces.com/ -- http://mail.python.org/mailman/listinfo/python-list
