James Stroud wrote: > Paul McGuire wrote: > > <[EMAIL PROTECTED]> wrote in message > > news:[EMAIL PROTECTED] > > > >>Hello, > >> > >> I cannot figure out a way to find a regular expression that would > >>match one and only one of these two strings: > [clip] > >>Any suggestion ? Thanks a bunch ! > >>Mathieu > >> > > > > A pyparsing approach is not as terse as regexp's, but it's not terribly long > > either. > > To second Paul's suggestion, usually, if the regex is not immediately > obvious, its probably better to look into parsing modules, pyparsing > being one of the most accessible modules (to me, anyways)--and well > worth learning.
I would say that it's better, before leaping to the implementation, to understand the problem. IOW, rough out the grammar first --- in the current case, not very complicated at all; the way I looked at it there are only two possible outcomes from the tokeniser (space and not-space) and only three non-terminal symbols (word, sentence, paragraph) -- then choose the implementation. > > However, in complicated applications, regex is usually still fun and > valuable as an intellectual exercise. Indeed. Better use of the mind and the CPU than distractions du jour like pseudorubiku or whatever it's called :-) Cheers, John -- http://mail.python.org/mailman/listinfo/python-list
