Thanks everybody for the insight that you have shared with me and the group.
As of now, I am abandoning this weekend project, and have started looking for something else :)) BTW, in the process of designing the semantics of the YAML description, I had to read through the Python RE module docs a few times and that has clarified my understanding of the regular expressions in general. So now I can atleast look at a regex and successfully try to figure out what its trying to say. Thanks and best regards, Vishal On Tue, Aug 10, 2010 at 8:57 AM, Dhananjay Nene <dhananjay.n...@gmail.com>wrote: > On Mon, Aug 9, 2010 at 5:04 PM, Vishal <vsapr...@gmail.com> wrote: > > > Hello fellas, > > > > I am trying to create a python function that can take an plain english > > description of a regular expression and return the regular expression to > > the > > caller. > > > > Currently I am thinking of the description in YAML format. So, we can > store > > the description as a raw string variable, which is passed on to this > > another > > function and output of that function is then passed to the 're' module. > > Following is a rather simplistic example: > > > > # a(b|c)d+e* > > > > re1 = """ > > > > - literal: 'a' > > - one_of: 'b,c' > > - one_or_more_of: 'd' > > - zero_or_more_of: 'e' > > """ > > > > myre = re.compile(getRegex(re1)) > > > > myre.search(...) > > > > etc. > > > > Does anyone think something of this sort would be of wider use? Do you > know > > already existing packages that can do it? What are the limitations that > you > > see to this approach? Does anyone think, having the declarative string in > > code, would make it more maintainable? > > > > The real struggle here is the complexity of modeling the problem you are > attempting to solve. RE syntax per se isn't the problem though it could be > recast a bit in favour of readability and grokkability away from brevity > (not that I am in favour of that). The issue is really the complexity of > the > diversity of situations that RE expressions attempt to model. Should you > wan't to attempt to support the entire range of scenarios that REs can > manage, I imagine the yaml will become excessively verbose to manage and > will eventually start suffering similar difficulties of grokkability that > complex REs end up with. While I don't think there's a good solution for > that, I think a victory if at all feasible could be better had through a > better modeling of how pattern matching expressions can be composed > (differently from current RE structures) rather than making the current > expression structures verbose and declarative. > > Dhananjay > > _______________________________________________ > > BangPypers mailing list > > BangPypers@python.org > > http://mail.python.org/mailman/listinfo/bangpypers > > > > > > -- > -------------------------------------------------------- > blog: http://blog.dhananjaynene.com > twitter: http://twitter.com/dnene > _______________________________________________ > BangPypers mailing list > BangPypers@python.org > http://mail.python.org/mailman/listinfo/bangpypers > -- Thanks and best regards, Vishal Sapre --- "So say...Day by day, in every way, I am getting better, better and better !!!" "A Strong and Positive attitude creates more miracles than anything else. Because...Life is 10% how you make it, and 90% how you take it" "Diamond is another piece of coal that did well under pressure” "May we do good and not evil. May we find forgiveness for ourself and forgive others. May we share freely, never taking more than we give." _______________________________________________ BangPypers mailing list BangPypers@python.org http://mail.python.org/mailman/listinfo/bangpypers
