# Source code for MDAnalysis.coordinates.null

    # -*- Mode: python; tab-width: 4; indent-tabs-mode:nil; coding:utf-8 -*-
    # vim: tabstop=4 expandtab shiftwidth=4 softtabstop=4
    #
    # MDAnalysis --- https://www.mdanalysis.org
    # Copyright (c) 2006-2017 The MDAnalysis Development Team and contributors
    # (see the file AUTHORS for the full list of names)
    #
    # Released under the Lesser GNU Public Licence, v2.1 or any higher version
    #
    # Please cite your use of MDAnalysis in published work:
    #
    # R. J. Gowers, M. Linke, J. Barnoud, T. J. E. Reddy, M. N. Melo, S. L. Seyler,
    # D. L. Dotson, J. Domanski, S. Buchoux, I. M. Kenney, and O. Beckstein.
    # MDAnalysis: A Python package for the rapid analysis of molecular dynamics
    # simulations. In S. Benthall and S. Rostrup editors, Proceedings of the 15th
    # Python in Science Conference, pages 102-109, Austin, TX, 2016. SciPy.
    # doi: 10.25080/majora-629e541a-00e
    #
    # N. Michaud-Agrawal, E. J. Denning, T. B. Woolf, and O. Beckstein.
    # MDAnalysis: A Toolkit for the Analysis of Molecular Dynamics Simulations.
    # J. Comput. Chem. 32 (2011), 2319--2327, doi:10.1002/jcc.21787
    #
    """
    Null output --- :mod:`MDAnalysis.coordinates.null`
    ==================================================

    The :class:`NullWriter` provides a Writer instance that behaves like
    any other writer but effectively ignores its input and does not write
    any output files. This is similar to writing to ``/dev/null``.

    This class exists to allow developers writing generic code and tests.

    Classes
    -------

    .. autoclass:: NullWriter
       :members:

    """
    from . import base

    class NullWriter(base.WriterBase):
        """A trajectory Writer that does not do anything.

        The NullWriter is the equivalent to ``/dev/null``: it behaves like
        a Writer but ignores all input. It can be used in order to
        suppress output.
        """

        format = "NULL"
        multiframe = True
        units = {"time": "ps", "length": "Angstrom"}

        def __init__(self, filename, **kwargs):
            pass

        def _write_next_frame(self, obj):
            try:
                atoms = obj.atoms
            except AttributeError:
                errmsg = "Input obj is neither an AtomGroup or Universe"
                raise TypeError(errmsg) from None