True inconsistency in Python
noemail at noemail4u.com
Thu Nov 13 13:33:28 CET 2003
On Wed, 12 Nov 2003 21:21:03 -0800, Erik Max Francis <max at alcyone.com>
>Scott Chapman wrote:
>> Historically Python has allowed <> 0 to equal true in evaluations.
>> <> 0 still evaluates to true in evaluations. However it doesn't equal
>> True. They are not interchangable. (Same with empty lists, etc.)
>That's because the proper way to test for truth does not use the True
>value at all. It is this:
> if x:
> if x == True:
Sort of like (stretchy) saying that if these are both True:
"a snake is green"
"a pearl is white"
that they are the same as each other.
They are both true, yet unrelated. You can say:
if "a snake is green": print 1
if "a pearl is white": print 2
and the prints would happen, but if you said
if "a snake is green" == "a pearl is white": print 3
the print would not happen.
More information about the Python-list