[Tutor] Surprising behaviour of optional argument

[Jose Amoreira]

Hi
On 07/17/2014 06:34 PM, Danny Yoo wrote:
>

> Yeah; the default value is not reevaluated between calls.  It's a common
> gotcha.  Here are a few links to read more:
>
> http://effbot.org/zone/default-values.htm
>
> http://docs.python-guide.org/en/latest/writing/gotchas/#mutable-default-arguments
>
> Good luck!
>

Aha, the object that stores the default value for the optional argument 
is created at the time of the execution of the function definition and 
mutable objects do mutate, so that's that. It makes a lot of sense.
Thanks, Danny