This section of the pyparsing wiki is open to public edits and contributions.

  • Here is a SQL parser that generates graphviz commands to graphically display tables and show foreign key links.
  • Here is a regex inverter that parses simple regular expressions, and creates a generator structure to generate strings that match the regex. Here are the test cases this inverter can handle:

To use this inverter, import the invert method, and call it as a generator, as in:
for s in invert("[A-Z]{3}\d{3}"):
 print s

Marek Kubica suggested a factory class to help manage setWhitespace calls without having to modify the global whitespace characters defined in the ParserElement class using setDefaultWhitespace. This suggestion evolved into the following wrapper class:
class SetWhitespace(object):
    def __init__(self, whitespacechars):
        self.whitespacechars = whitespacechars
    def __call__(self,pyparsing_expr):
        return pyparsing_expr
noNLskipping = SetWhitespace(' \t\r')
word = noNLskipping(Word(alphas))

Any comments? Should I just add this to pyparsing?

pyparsing_helper is a new GUI for troubleshooting your pyparsing grammars.

You can easy_install it with
easy_install pyparsing_helper

Similarly, reinteract is a general-purpose GUI interactive Python session that can be used to tweak pyparsing grammars in development, and is a more sophisticated tool overall.