[Python-ideas] Documenting Python warts

Wed Jan 2 04:25:35 CET 2013

On Wed, Jan 2, 2013 at 1:16 PM, Oleg Broytman <phd at phdru.name> wrote:
> On Wed, Jan 02, 2013 at 11:07:58AM +1000, Nick Coghlan <ncoghlan at gmail.com> wrote:
>> Mutable default arguments make perfect sense once you
>> understand the difference between compile time, definition time and
>> execution time for a function. Defaults are evaluated at definition
>> time, thus they are necessarily shared across all invocations of the
>> function.
>> I.e., users have to understand the current implementation. Mutable
> defaults are not a language design choice, they are dictated by the
> implementation, right?

No, they're not an implementation accident, they're part of the
language design. It's OK if you don't like them, but please stop
claiming they're a CPython implementation artifact.
Cheers,
Nick.
--
Nick Coghlan | ncoghlan at gmail.com | Brisbane, Australia