question about True values

Steve Holden steve at holdenweb.com
Thu Oct 26 01:05:21 CEST 2006


skip at pobox.com wrote:
>     John> I'm a little confused. Why doesn't s evaluate to True in the first
>     John> part, but it does in the second? Is the first statement something
>     John> different?
> 
>     >>> s = 'hello'
>     >>> s == True
>     False
>     >>> if s:
>     ...         print 'hi'
>     hi
> 
> s is not equal to the boolean object True, but it also doesn't evaluate to
> the string class's "nil" value.  Each of the builtin types has such an
> "empty" or "nil" value:
> 
>     string              ""
>     list                []
>     tuple               ()
>     dict                {}
>     int                 0
>     float               0.0
>     complex             0j
>     set                 set()
> 
> Any other value besides the above will compare as "not false".
> 

And today's question for the novices is: which Python type did Skip miss 
from the above list?

regards
  Steve
-- 
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