mk wrote: > Hello everyone, > > print hosts > hosts = [ s.strip() for s in hosts if s is not '' and s is not None and > s is not '\n' ] > print hosts > > ['9.156.44.227\n', '9.156.46.34 \n', '\n'] > ['9.156.44.227', '9.156.46.34', ''] > > Why does the hosts list after list comprehension still contain '' in > last position? > > I checked that: > > print hosts > hosts = [ s.strip() for s in hosts if s != '' and s != None and s != '\n' > ] print hosts > > ..works as expected: > > ['9.156.44.227\n', '9.156.46.34 \n', '\n'] > ['9.156.44.227', '9.156.46.34'] > > > Are there two '\n' strings in the interpreter's memory or smth so the > identity check "s is not '\n'" does not work as expected? > > This is weird. I expected that at all times there is only one '\n' > string in Python's cache or whatever that all labels meant by the > programmer as '\n' string actually point to. Is that wrong assumption?
Yes. Never use "is" unless you know 100% that you are talking about the same object, not just equality. Diez -- http://mail.python.org/mailman/listinfo/python-list
