Adding a new module
===================

Each module needs an `__init__.py` file and a `tests` folder that also
contains an `__init__.py` file. For a module, a simple one may look
like this::

    r"""
    A module (:mod:`skbio.module`)
    ==============================

    .. currentmodule:: skbio.module

    Documentation for this module.
    """

    # ----------------------------------------------------------------------------
    # Copyright (c) 2013--, scikit-bio development team.
    #
    # Distributed under the terms of the Modified BSD License.
    #
    # The full license is in the file LICENSE.txt, distributed with this software.
    # ----------------------------------------------------------------------------

    from skbio.util import TestRunner
    test = TestRunner(__file__).test

Usually, some functionality from the module will be made accessible by
importing it in `__init__.py`. It's convenient to use explicit
relative imports (`from .implementation import compute`), so that
functionality can be neatly separated in different files but the user
doesn't face a deeply nested package: `from skbio.module import
compute` instead of `from skbio.module.implementation import compute`.

Inside the tests folder, a simpler `__init__.py` works fine (it is
necessary so that all tests can be run after installation)::

    # ----------------------------------------------------------------------------
    # Copyright (c) 2013--, scikit-bio development team.
    #
    # Distributed under the terms of the Modified BSD License.
    #
    # The full license is in the file LICENSE.txt, distributed with this software.
    # ----------------------------------------------------------------------------

Finally, remember to also follow the :doc:`doc_guide`.
