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``reverse``
===========
The ``reverse`` filter reverses a sequence, a mapping, or a string:
.. code-block:: twig
{% for user in users|reverse %}
...
{% endfor %}
{{ '1234'|reverse }}
{# outputs 4321 #}
.. tip::
For sequences and mappings, numeric keys are not preserved. To reverse
them as well, pass ``true`` as an argument to the ``reverse`` filter:
.. code-block:: twig
{% for key, value in {1: "a", 2: "b", 3: "c"}|reverse %}
{{ key }}: {{ value }}
{%- endfor %}
{# output: 0: c 1: b 2: a #}
{% for key, value in {1: "a", 2: "b", 3: "c"}|reverse(true) %}
{{ key }}: {{ value }}
{%- endfor %}
{# output: 3: c 2: b 1: a #}
.. note::
It also works with objects implementing the `Traversable`_ interface.
Arguments
---------
* ``preserve_keys``: Preserve keys when reversing a mapping or a sequence.
.. _`Traversable`: https://secure.php.net/Traversable