The DRY alternative to __all__

To install the exports package, you can use python-exports on PyPI:

pip install python-exports

>>> from exports import export

Now you can use it to add to __all__ as

• function decorator

  >>> @export
  ... def spam():
  ...     ...

• class decorator:

  >>> @export
  ... class Ham:
  ...     ...

• by name:

  >>> from functools import reduce as fold
  >>> export('fold')

If the module has no __all__, it is created. Otherwise, __all__ is converted to a list, and the export is appended.

Exporting a function or class directly relies on the __name__ attribute, so consider the following example:

>>> def eggs():
...     ...
>>> fake_eggs = eggs

If we want to export fake_eggs, then this will not work:

>>> export(fake_eggs)  # BAD: this will add `'eggs'` to `__all__`

In such cases, use the name instead:

>>> export('fake_eggs')  # GOOD

You'll be safe if you either

• decorate a function or a class directly with @export,
• pass the name string when using plain export('...') calls.