On Fri, 07 Apr 2006 15:50:53 +0200, WENDUM Denis 47.76.11 (agent) wrote:
> While testing recursive algoritms dealing with generic lists I stumbled > on infinite loops which were triggered by the fact that (at least for my > version of Pyton) characters contain themselves. A "character" is just a string of length 1. [snip] > Leading to paradoxes and loops objects which contain themselves (and > other kinds of monsters) are killed in set theory with the Axiom of > Foundation:=) Let me see if I understand you... you would like behaviour like this? >>> 'a' in 'bbabb' True >>> 'a' in 'bbab' True >>> 'a' in 'bab' True >>> 'a' in 'ab' True >>> 'a' in 'a' False # not the real result Ain't going to happen. > But let's go back to more earthly matters. I couldn't find any clue in a > python FAQ after having googled with the following "Python strings FAQ" > about why this design choice and how to avoid falling in this trap > without having to litter my code everywhere with tests for stringiness > each time I process a generic list of items. > > Any hints would be appreciated. I think that if you want to do work with sets, use sets, not strings. In Python 2.3, you need: >>> import sets In Python 2.4, Sets (note the initial capital) are a built-in. -- Steven. -- http://mail.python.org/mailman/listinfo/python-list
