Terry Reedy wrote: > Steve Holden wrote: >> Terry Reedy wrote: > >>> In 2.x, the *names* 'True' and 'False' can be rebound because bool is >>> new and people write >>> try: >>> False,True >>> except NameError: >>> False,True = 0,1 >>> >>> to make code back compatible. >>> >> I would claim that the ability to rebind True and False is a simple bug, >> though one not likely to be fixed in an 2.x release. The code above >> doesn't rebind True and False in interpreters that have them ... > > In pre-bool 2.x, people never wrote the above but sometime wrote > False,True = 0,1 > Right. This is the use case I overlooked.
> To me it is hardly a bug to not gratuitously break substantial amounts > of proper code. > I quite agree. I take it all back! >>> Back before rebinding 'None' was prohibited, 'is None' was not >>> completely guaranteed either (absent reading the rest of a file to be >>> sure no rebinding would be done). >>> >> And that was a bug too, in this case one that *was* removed in 2.4, I >> believe. Don't have 2.3 lying around just now. > > Unlike with True and False, the devs could not think of or find any > proper use case for rebinding None and judged that the new prohibition > would break very little if any code. As far as I know, they were correct. > Indeed they were. regards Steve -- Steve Holden +1 571 484 6266 +1 800 494 3119 Holden Web LLC http://www.holdenweb.com/ -- http://mail.python.org/mailman/listinfo/python-list
