On Oct 13, 9:40 am, [EMAIL PROTECTED] wrote: > I'm looking for a function which, given a regexp re and and a string > str, returns whether re won't match any string starting with str. (so > it would always return False if str is "" or if str itself matches re > -- but that are only the easy cases).
Wow, that's a pretty problem. > Any ideas or prior art on how to get this function? An idea, which I haven't explored well enough: Parse the regexp, and recursively descend the parse tree; for each node on the recursive descent, generate the regexp that follows the descent to end at that node and ask if it matches the string. If it matches, return 'False'. If the recursion ends without ever matching, return 'True'. There are a few questions on how to do that. I don't know how to parse the regexp (but I know how to start and am confident that it'd be easy); I don't know how to generate the regexp given a descent path (but I think I could do it). I'm also not sure this is correct, but it's not a homework assignment for me, so I'm not worried. > Peter -Wm -- http://mail.python.org/mailman/listinfo/python-list
