On Oct 6, 8:34 pm, Neil Cerutti <[EMAIL PROTECTED]> wrote: > And in the original case, I'd agree that "if X.has_key():" is > quite clear, already yielding a boolian value, and so doesn't > need to be tested for if it's False. But I wouldn't like to test > for an empty list or for None implicitly.
I agree that predicates are explicit in themselves, if they are named intuitively like "has_key". I assumed that the OP was upset about "is False" not that an explicit check was done on a predicate method. On Oct 6, 8:38 pm, Gabriel Genellina <[EMAIL PROTECTED]> wrote: > It's not about style or being pythonic: a condition may be false, but > not the False object itself, so writing > if something is False: > is the wrong way to test if something is false (isn't clear? :) ) Yes, I understand, and it's true that in a mixed context it could bite you (or you could check equality rather than identity), but assuming a strictly boolean context you don't have that problem (or perhaps you even *want* to differentiate between False, None and 0 in a mixed context). Ps. I mostly use the "if (not) cond" form. But I take the style guide as a, well, *guide*, rather than a style *law* and I tend to get annoyed when people get religious about things like that. Subjective taste, be it GvR's or the Pope's, is -- subjective. On the other hand, if lightening is flashing and seas are parting and stuff, I don;t tend to argue too much in that case. ;) Regards, Jordan -- http://mail.python.org/mailman/listinfo/python-list
