On 03Apr2012 15:08, Ethan Furman <ethan@stoneleaf.us> wrote: | Cameron Simpson wrote: | > get_clock already has two arguments - you can optionally hand it a clock | > list - that's used by monotonic_clock() and hires_clock(). | | def get_clock(*flags, *, clocklist=None): I presume that bare "*," is a typo. Both my python2 and python3 commands reject it. [...] | wanted = 0 | for flag in flags: | wanted |= flag [...] I could do this. I think I'm -0 on it, because it doesn't seem more expressive to my eye than the straight make-a-bitmask "|" form. Other opinions? | Would need to make *flags change to the other *_clock functions. Yep. | > The return of None is very deliberate. I _want_ user specified fallback | > to be concise and easy. The example: | > clock = get_clock(MONOTONIC|HIRES) or get_clock(MONOTONIC) | | Which would become: | clock = get_clock(MONOTONIC, HIGHRES) or get_clock(MONOTONIC) | | +1 to returning None | | > Exceptions are all very well when there is just one thing to do: parse | > this or fail, divide this by that or fail. If fact they're the very | > image of "do this one thing or FAIL". They are not such a good match for do | > this thing or that thing or this other thing. Another thought that occurred in the shower was that get_clock() et al are inquiry functions, and returning None is very sensible there. monotonic() et al are direct use functions, which should raise an exception if unavailable so that code like: t0 = monotonic() ....... t1 = monotonic() does not become littered with checks for special values like None. I consider this additional reason to return None from get_clock(). Cheers, -- Cameron Simpson <cs@zip.com.au> DoD#743 http://www.cskk.ezoshosting.com/cs/ DON'T DRINK SOAP! DILUTE DILUTE! OK! - on the label of Dr. Bronner's Castile Soap