On Sat, 28 Apr 2007 14:33:23 +0200, Szabolcs wrote:
> Newbie question:
>
> Why is 1 == True and 2 == True (even though 1 != 2),
> but 'x' != True (even though if 'x': works)?
Everything in Python has a truth-value. So you can always do this:
if some_object:
print "if clause is true"
else:
print "else clause"
no matter what some_object is.
The constants True and False are a pair of values of a special type bool.
The bool type is in fact a sub-class of int:
>>> issubclass(bool, int)
True
>>> 7 + False
7
>>> 7 + True
8
Can you guess what values True and False are "under the hood"?
>>> 1 == True
True
>>> 0 == False
True
>>> 2 == True
False
>>> if 2:
... print "2 is considered true"
...
2 is considered true
If you are getting different results, the chances are that you have
accidentally reassigned that names True or False:
>>> True = 2 # DON'T DO THIS!!!
>>> 2 == True
True
--
Steven.
--
http://mail.python.org/mailman/listinfo/python-list
