[Python-Dev] an alternative to embedding policy in PEP 418 (was: PEP 418: Add monotonic clock)

[Ethan Furman]

Lennart Regebro wrote:
> On Tue, Apr 3, 2012 at 18:07, Ethan Furman <ethan at stoneleaf.us> wrote:
>> What's unclear about returning None if no clocks match?
> 
> Nothing, but having to check error values on return functions are not
> what you typically do in Python. Usually, Python functions that fail
> raise an error. Please don't force Python users to write pseudo-C code
> in Python.

You mean like the dict.get() function?

--> repr({}.get('missing'))
'None'

Plus, failure mode is based on intent:  if the intent is "Give a clock 
no matter what", then yes, an exception when that's not possible is the 
way to go.

But if the intent is "Give me a clock that matches this criteria" then 
returning None is perfectly reasonable.

~Ethan~