On Thu, Apr 5, 2012 at 10:34 PM, Oleg Broytman <phd@phdru.name> wrote:
Why doesn't open() return None for a non-existing file? or socket.gethostbyname() for a non-existing name?
That's not an answer to my question, because those calls have very important use cases where the user knows the object exists (and in fact in some cases open() will create it for him), so that failure to exist is indeed a (user) error (such as a misspelling). I find it hard to imagine use cases where "file = open(thisfile) or open(thatfile)" makes sense. Not even for the case where thisfile == 'script.pyc' and thatfile == 'script.py'. The point of the proposed get_clock(), OTOH, is to ask if an object with certain characteristics exists, and the fact that it returns the clock rather than True if found is a matter of practical convenience. Precisely because "clock = get_clock(best) or get_clock(better) or get_clock(acceptable)" does make sense.