Brett Hoerner wrote:
> [EMAIL PROTECTED] wrote:
[...]
> "or" returns the first true element, anything but False or None, I
> think... so 'food' (a string) is true, and always will return in that
> code.
Just in case newbies are reading: in Python several different values are
considered false in the context of an "if" statement. These include
False # Boolean False
0 # The integer zero
0.0 # Floating-point zero
(0+0j) # Complex zero
None # The None object
[] # The empty list
() # The empty tuple
{} # The empty dictionary
This is mainly to allow the convenience of writing
if thing:
...
However, one has to be careful that code that needs to treat None
differently from [] uses explicit testing such as
if thing is None:
...
You can also construct your own classes so their instances evaluate to
True or False according to your needs.
regards
Steve
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