Don't hide common classes / hide imports

[ep12]

If trying to create a higher level script with custom classes, it is helpful to have direct access to the common classes of SoundCard, e.g.:

import soundcard as sc
# ...
class AudioChannel(object):
    def play(self, speaker):
        assert isinstance(speaker, sc.Speaker), 'speaker must be a speaker'
        # ...
```
Currently, those classes are hidden and not accessible. However, internals (imports) like cffi, re, os, ... should not be visible to the developer trying out that package using ipython or similar.

[bastibe]

I don't quite understand your comment. What exactly are you trying to do, and what do you think SoundCard is doing wrong?

[ep12]

It isn't doing anything wrong, but if one wants to explore a module, it is helpful to hide imports that the developer does not need to see. I changed everything except numpy to start with underscores:
os -> _os
time -> _time
And I renamed _Speaker, _Microphone, _Player and _Recorder so that they are usable. Before,

import soundcard as sc
sc._Speaker

raised an AttributeError: the module has no attribute _Speaker.
My fork here contains those changes and some linter eyecandy (visual indentation, some new docstrings) but I'm still working on it. I'll create a pull request when I'm happy with it.

[bastibe]

There's a reason for the underscores on _Speaker, _Microphone, _Player, and _Recorder: They are not meant to be used by users. There is essentially no way for a user to supply them with their required arguments. That's why they are hidden.

As for renaming common imports, do you have a reference for this? I know this practice exists, but I find it profoundly ugly. Could you accomplish a similar goal by specifying an __all__?

[levic]

What exactly are you trying to do

One use case: I was trying to use type annotations for functions that passed around _Microphone and _Speaker objects but I couldn't because they're not exported.

Could you accomplish a similar goal by specifying an __all__?

Yes, __all__ can include identifiers with underscores; the name alone indicates that it's an internal identifier even if it's exported.

The main downside of __all__ is that it's extra work: you need to keep it up to date for every implementation (pulseaudio/coreaudio/mediafoundation) and then again in __init__.py (although the code is identical between them all).

[levic]

For reference, I've been using this:

__all__ = (
	'_Microphone',
	'_Player',
	'_Recorder',
	'_Speaker',
	'all_microphones',
	'all_speakers',
	'default_microphone',
	'default_speaker',
	'get_microphone',
	'get_speaker',
)

(those are the classes that appears to be common, but I've only tested on windows)

[bastibe]

Yes, type annotations are a good reason for accessing these. But then, I think import soundcard._Microphone is a sensible solution to this problem. It's only four imports, after all.

[bastibe]

If anyone cares enough about this to contribute a pull request, I'll be happy to merge it.