Steve - Wow, this is a pretty dense pyparsing program. You are really pushing the envelope in your use of ParseResults, dicts, etc., but pretty much everything seems to be working.
I still don't know the BNF you are working from, but here are some other "shots in the dark": 1. I'm surprised func_word does not permit numbers anywhere in the body. Is this just a feature you have not implemented yet? As long as func_word does not start with a digit, you can still define one unambiguously to allow numbers after the first character if you define func_word as func_word = _pp.Word(func_chars,func_chars+_pp.nums) Perhaps similar for syn_word as well. 2. Is coord an optional sub-element of a func? If so, you might want to group them so that they stay together, something like: coord_tag = _pp.Optional(_pp.Combine(coord_sep + num_word)) func_tags = _pp.ZeroOrMore(_pp.Group(tag_sep + func_word+coord_tag)) You might also add a default value for coord_tag if none is supplied, to simplify your parse action? coord_tag = _pp.Optional(_pp.Combine(coord_sep + num_word),None) Now the coords and funcs will be kept together. 3. Of course, you are correct in using Combine to ensure that you only accept adjacent characters. But you only need to use it at the outermost level. 4. You can use several dict-like functions directly on a ParseResults object, such as keys(), items(), values(), in, etc. Also, the [] notation and the .attribute notation are nearly identical, except that [] refs on a missing element will raise a KeyError, .attribute will always return something. For instance, in your example, the getTag() parse action uses dict.pop() to extract the 'coord' field. If coord is present, you could retrieve it using "tokens['coord']" or "tokens.coord". If coord is missing, "tokens['coord']" will raise a KeyError, but tokens.coord will return an empty string. If you need to "listify" a ParseResults, try calling asList(). It's not clear to me what if any further help you are looking for, now that your initial question (about StringEnd()) has been answered. But please let us know how things work out. -- Paul -- http://mail.python.org/mailman/listinfo/python-list
