Set a flag on the function or a global?

[Mark Lawrence]

On 16/06/2015 00:57, Steven D'Aprano wrote:
> I have a function in a module which is intended to be used by importing
> that name alone, then used interactively:
>
>      from module import edir
>      edir(args)
>
>
> edir is an enhanced version of dir, and one of the enhancements is that
> you can filter out dunder methods. I have reason to believe that people
> are split on their opinion on whether dunder methods should be shown by
> default or not: some people want to see them, others do not. Since edir
> is meant to be used interactively, I want to give people a setting to
> control whether they get dunders by default or not.
>
> I have two ideas for this, a module-level global, or a flag set on the
> function object itself. Remember that the usual way of using this will be
> "from module import edir", there are two obvious ways to set the global:
>
> import module
> module.dunders = False
>
> # -or-
>
> edir.__globals__['dunders'] = False
>
>
> Alternatively, I can use a flag set on the function object itself:
>
> edir.dunders = False
>
>
> Naturally you can always override the default by explicitly specifying a
> keyword argument edir(obj, dunders=flag).
>
> Thoughts and feedback? Please vote: a module global, or a flag on the
> object? Please give reasons, and remember that the function is intended
> for interactive use.
>
>

For interactive use I'd be perfectly happy with just the keyword 
argument.  Why bother toggling something when I can explicitly set it in 
the call each and every time?  If I have to choose it's a flag on the 
object, just no competition.

-- 
My fellow Pythonistas, ask not what our language can do for you, ask
what you can do for our language.

Mark Lawrence