Bjoern Schliessmann <[EMAIL PROTECTED]> writes:
> Bruno Desthuilliers wrote:
> > Shawn Milo a écrit :
>
> >> if recs.has_key(piid) is False:
> >
> > 'is' is the identity operator - practically, in CPython, it
> > compares memory addresses. You *dont* want to use it here.
>
> It's recommended to use "is None"; why not "is False"? Are there
> multiple False instances or is False generated somehow?
I'd recommend against using "is False" simply because it's more
confusing. This is better::
if not recs.has_key(piid): # [1]
Moreover, any 'if' statement expects a boolean expression *anyway*, so
there's no point testing for identity against False. Otherwise, the
following would be just as reasonable::
if (recs.has_key(piid) is False) is True:
Or perhaps:
if (((((recs.has_key(piid) is False) is True) is False) is False) is True):
[1]: yes, this is even better written as 'if not piid in recs', but
that's beside the point for this discussion.
--
\ "To be is to do" -- Plato |
`\ "To do is to be" -- Aristotle |
_o__) "Do be do be do" -- Sinatra |
Ben Finney
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