magnum-bindings/doc/python/corrade.containers.rst

..
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..

.. doctest setup
    >>> from corrade import containers

.. py:class:: corrade.containers.ArrayView

    Provides one-dimensional tightly packed view on a memory range. Convertible
    both from and to Python objects supporting the Buffer Protocol, with one
    dimension and stride of :py:`1`. See :ref:`StridedArrayView1D` and others
    for more generic views. :ref:`ArrayView` is immutable, see
    :ref:`MutableArrayView` for the mutable alterantive. All slicing operations
    are supported, specifying a non-trivial stride will return
    :ref:`StridedArrayView1D` instead of :ref:`ArrayView`. Example usage:

    .. code:: pycon

        >>> a = b'hello'
        >>> b = containers.ArrayView(a)
        >>> b[2]
        'l'
        >>> bytes(b[1:4])
        b'ell'

    `Memory ownership and reference counting`_
    ==========================================

    Unlike in C++, the view keeps a reference to the original memory owner
    object in the :ref:`owner` field, meaning that calling :py:`del` on the
    original object will *not* invalidate the view. Slicing a view creates a
    new view referencing the same original object, without any dependency on
    the previous view. That means a long chained slicing operation will not cause
    increased memory usage.

    .. code:: pycon

        >>> b.owner is a
        True
        >>> b[1:4][:-1].owner is a
        True

    The :py:`owner` is :py:`None` if the view is empty.

    `Comparison to Python's memoryview`_
    ====================================

    The :ref:`ArrayView` class is equivalent to one-dimensional
    :ref:`memoryview` with a stride of :py:`1`. For multiple dimensions and
    non-trivial strides, :ref:`StridedArrayView1D` and friends provide a
    superset of :ref:`memoryview` features.

.. py:class:: corrade.containers.MutableArrayView

    Equivalent to :ref:`ArrayView`, but implementing :ref:`__setitem__()` as
    well.

.. py:class:: corrade.containers.StridedArrayView1D

    Provides one-dimensional read-only view on a memory range with custom
    stride values. See :ref:`StridedArrayView2D`, :ref:`StridedArrayView3D`,
    :ref:`MutableStridedArrayView1D` and others for multi-dimensional and
    mutable equivalents.

    `Comparison to Python's memoryview`_
    ====================================

    The :ref:`StridedArrayView1D` and its multi-dimensional variants are
    equivalent to any :ref:`memoryview`, but additionally supporting
    multi-dimensional slicing as well (which raises :ref:`NotImplementedError`
    in Py3.7 :ref:`memoryview`).

.. py:class:: corrade.containers.MutableStridedArrayView1D

    Equivalent to :ref:`StridedArrayView1D`, but implementing
    :ref:`__setitem__()` as well.

.. py:class:: corrade.containers.StridedArrayView2D

    See :ref:`StridedArrayView1D` for more information.

.. py:class:: corrade.containers.MutableStridedArrayView2D

    See :ref:`StridedArrayView1D` and :ref:`MutableStridedArrayView1D` for more
    information.

.. py:class:: corrade.containers.StridedArrayView3D

    See :ref:`StridedArrayView1D` for more information.

.. py:class:: corrade.containers.MutableStridedArrayView3D

    See :ref:`StridedArrayView1D` and :ref:`MutableStridedArrayView1D` for more
    information.