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builtins.txt
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.. _ref-templates-builtins:
==================================
Built-in template tags and filters
==================================
This document describes Django's built-in template tags and filters. It is
recommended that you use the :ref:`automatic documentation
<template-built-in-reference>`, if available, as this will also include
documentation for any custom tags or filters installed.
.. _ref-templates-builtins-tags:
Built-in tag reference
----------------------
.. highlightlang:: html+django
.. templatetag:: autoescape
autoescape
~~~~~~~~~~
.. versionadded:: 1.0
Control the current auto-escaping behavior. This tag takes either ``on`` or
``off`` as an argument and that determines whether auto-escaping is in effect
inside the block.
When auto-escaping is in effect, all variable content has HTML escaping applied
to it before placing the result into the output (but after any filters have
been applied). This is equivalent to manually applying the ``escape`` filter
to each variable.
The only exceptions are variables that are already marked as "safe" from
escaping, either by the code that populated the variable, or because it has had
the ``safe`` or ``escape`` filters applied.
.. templatetag:: block
block
~~~~~
Define a block that can be overridden by child templates. See
:ref:`Template inheritance <template-inheritance>` for more information.
.. templatetag:: comment
comment
~~~~~~~
Ignore everything between ``{% comment %}`` and ``{% endcomment %}``
.. templatetag:: csrf_token
csrf_token
~~~~~~~~~~
.. versionadded:: 1.1.2
In the Django 1.1.X series, this is a no-op tag that returns an empty string.
It exists to ease the transition to Django 1.2, in which it is used for CSRF
protection.
.. templatetag:: cycle
cycle
~~~~~
.. versionchanged:: 1.0
Cycle among the given strings or variables each time this tag is encountered.
Within a loop, cycles among the given strings each time through the
loop::
{% for o in some_list %}
<tr class="{% cycle 'row1' 'row2' %}">
...
</tr>
{% endfor %}
You can use variables, too. For example, if you have two template variables,
``rowvalue1`` and ``rowvalue2``, you can cycle between their values like this::
{% for o in some_list %}
<tr class="{% cycle rowvalue1 rowvalue2 %}">
...
</tr>
{% endfor %}
Yes, you can mix variables and strings::
{% for o in some_list %}
<tr class="{% cycle 'row1' rowvalue2 'row3' %}">
...
</tr>
{% endfor %}
In some cases you might want to refer to the next value of a cycle from
outside of a loop. To do this, just give the ``{% cycle %}`` tag a name, using
"as", like this::
{% cycle 'row1' 'row2' as rowcolors %}
From then on, you can insert the current value of the cycle wherever you'd like
in your template::
<tr class="{% cycle rowcolors %}">...</tr>
<tr class="{% cycle rowcolors %}">...</tr>
You can use any number of values in a ``{% cycle %}`` tag, separated by spaces.
Values enclosed in single (``'``) or double quotes (``"``) are treated as
string literals, while values without quotes are treated as template variables.
Note that the variables included in the cycle will not be escaped.
This is because template tags do not escape their content. Any HTML or
Javascript code contained in the printed variable will be rendered
as-is, which could potentially lead to security issues.
If you need to escape the variables in the cycle, you must do so
explicitly::
{% filter force_escape %}
{% cycle var1 var2 var3 %}
{% endfilter %}
For backwards compatibility, the ``{% cycle %}`` tag supports the much inferior
old syntax from previous Django versions. You shouldn't use this in any new
projects, but for the sake of the people who are still using it, here's what it
looks like::
{% cycle row1,row2,row3 %}
In this syntax, each value gets interpreted as a literal string, and there's no
way to specify variable values. Or literal commas. Or spaces. Did we mention
you shouldn't use this syntax in any new projects?
.. templatetag:: debug
debug
~~~~~
Output a whole load of debugging information, including the current context and
imported modules.
.. templatetag:: extends
extends
~~~~~~~
Signal that this template extends a parent template.
This tag can be used in two ways:
* ``{% extends "base.html" %}`` (with quotes) uses the literal value
``"base.html"`` as the name of the parent template to extend.
* ``{% extends variable %}`` uses the value of ``variable``. If the variable
evaluates to a string, Django will use that string as the name of the
parent template. If the variable evaluates to a ``Template`` object,
Django will use that object as the parent template.
See :ref:`template-inheritance` for more information.
.. templatetag:: filter
filter
~~~~~~
Filter the contents of the variable through variable filters.
Filters can also be piped through each other, and they can have arguments --
just like in variable syntax.
Sample usage::
{% filter force_escape|lower %}
This text will be HTML-escaped, and will appear in all lowercase.
{% endfilter %}
.. templatetag:: firstof
firstof
~~~~~~~
Outputs the first variable passed that is not False, without escaping.
Outputs nothing if all the passed variables are False.
Sample usage::
{% firstof var1 var2 var3 %}
This is equivalent to::
{% if var1 %}
{{ var1|safe }}
{% else %}{% if var2 %}
{{ var2|safe }}
{% else %}{% if var3 %}
{{ var3|safe }}
{% endif %}{% endif %}{% endif %}
You can also use a literal string as a fallback value in case all
passed variables are False::
{% firstof var1 var2 var3 "fallback value" %}
Note that the variables included in the firstof tag will not be
escaped. This is because template tags do not escape their content.
Any HTML or Javascript code contained in the printed variable will be
rendered as-is, which could potentially lead to security issues.
If you need to escape the variables in the firstof tag, you must do so
explicitly::
{% filter force_escape %}
{% firstof var1 var2 var3 "fallback value" %}
{% endfilter %}
.. templatetag:: for
for
~~~
Loop over each item in an array. For example, to display a list of athletes
provided in ``athlete_list``::
<ul>
{% for athlete in athlete_list %}
<li>{{ athlete.name }}</li>
{% endfor %}
</ul>
You can loop over a list in reverse by using ``{% for obj in list reversed %}``.
.. versionadded:: 1.0
If you need to loop over a list of lists, you can unpack the values
in each sub-list into individual variables. For example, if your context
contains a list of (x,y) coordinates called ``points``, you could use the
following to output the list of points::
{% for x, y in points %}
There is a point at {{ x }},{{ y }}
{% endfor %}
This can also be useful if you need to access the items in a dictionary.
For example, if your context contained a dictionary ``data``, the following
would display the keys and values of the dictionary::
{% for key, value in data.items %}
{{ key }}: {{ value }}
{% endfor %}
The for loop sets a number of variables available within the loop:
========================== ================================================
Variable Description
========================== ================================================
``forloop.counter`` The current iteration of the loop (1-indexed)
``forloop.counter0`` The current iteration of the loop (0-indexed)
``forloop.revcounter`` The number of iterations from the end of the
loop (1-indexed)
``forloop.revcounter0`` The number of iterations from the end of the
loop (0-indexed)
``forloop.first`` True if this is the first time through the loop
``forloop.last`` True if this is the last time through the loop
``forloop.parentloop`` For nested loops, this is the loop "above" the
current one
========================== ================================================
for ... empty
^^^^^^^^^^^^^
.. versionadded:: 1.1
The ``for`` tag can take an optional ``{% empty %}`` clause that will be
displayed if the given array is empty or could not be found::
<ul>
{% for athlete in athlete_list %}
<li>{{ athlete.name }}</li>
{% empty %}
<li>Sorry, no athlete in this list!</li>
{% endfor %}
<ul>
The above is equivalent to -- but shorter, cleaner, and possibly faster
than -- the following::
<ul>
{% if athlete_list %}
{% for athlete in athlete_list %}
<li>{{ athlete.name }}</li>
{% endfor %}
{% else %}
<li>Sorry, no athletes in this list.</li>
{% endif %}
</ul>
.. templatetag:: if
if
~~
The ``{% if %}`` tag evaluates a variable, and if that variable is "true" (i.e.
exists, is not empty, and is not a false boolean value) the contents of the
block are output::
{% if athlete_list %}
Number of athletes: {{ athlete_list|length }}
{% else %}
No athletes.
{% endif %}
In the above, if ``athlete_list`` is not empty, the number of athletes will be
displayed by the ``{{ athlete_list|length }}`` variable.
As you can see, the ``if`` tag can take an optional ``{% else %}`` clause that
will be displayed if the test fails.
``if`` tags may use ``and``, ``or`` or ``not`` to test a number of variables or
to negate a given variable::
{% if athlete_list and coach_list %}
Both athletes and coaches are available.
{% endif %}
{% if not athlete_list %}
There are no athletes.
{% endif %}
{% if athlete_list or coach_list %}
There are some athletes or some coaches.
{% endif %}
{% if not athlete_list or coach_list %}
There are no athletes or there are some coaches (OK, so
writing English translations of boolean logic sounds
stupid; it's not our fault).
{% endif %}
{% if athlete_list and not coach_list %}
There are some athletes and absolutely no coaches.
{% endif %}
``if`` tags don't allow ``and`` and ``or`` clauses within the same tag, because
the order of logic would be ambiguous. For example, this is invalid::
{% if athlete_list and coach_list or cheerleader_list %}
If you need to combine ``and`` and ``or`` to do advanced logic, just use nested
``if`` tags. For example::
{% if athlete_list %}
{% if coach_list or cheerleader_list %}
We have athletes, and either coaches or cheerleaders!
{% endif %}
{% endif %}
Multiple uses of the same logical operator are fine, as long as you use the
same operator. For example, this is valid::
{% if athlete_list or coach_list or parent_list or teacher_list %}
.. templatetag:: ifchanged
ifchanged
~~~~~~~~~
Check if a value has changed from the last iteration of a loop.
The 'ifchanged' block tag is used within a loop. It has two possible uses.
1. Checks its own rendered contents against its previous state and only
displays the content if it has changed. For example, this displays a list of
days, only displaying the month if it changes::
<h1>Archive for {{ year }}</h1>
{% for date in days %}
{% ifchanged %}<h3>{{ date|date:"F" }}</h3>{% endifchanged %}
<a href="{{ date|date:"M/d"|lower }}/">{{ date|date:"j" }}</a>
{% endfor %}
2. If given a variable, check whether that variable has changed. For
example, the following shows the date every time it changes, but
only shows the hour if both the hour and the date has changed::
{% for date in days %}
{% ifchanged date.date %} {{ date.date }} {% endifchanged %}
{% ifchanged date.hour date.date %}
{{ date.hour }}
{% endifchanged %}
{% endfor %}
The ``ifchanged`` tag can also take an optional ``{% else %}`` clause that
will be displayed if the value has not changed::
{% for match in matches %}
<div style="background-color:
{% ifchanged match.ballot_id %}
{% cycle "red" "blue" %}
{% else %}
grey
{% endifchanged %}
">{{ match }}</div>
{% endfor %}
.. templatetag:: ifequal
ifequal
~~~~~~~
Output the contents of the block if the two arguments equal each other.
Example::
{% ifequal user.id comment.user_id %}
...
{% endifequal %}
As in the ``{% if %}`` tag, an ``{% else %}`` clause is optional.
The arguments can be hard-coded strings, so the following is valid::
{% ifequal user.username "adrian" %}
...
{% endifequal %}
It is only possible to compare an argument to template variables or strings.
You cannot check for equality with Python objects such as ``True`` or
``False``. If you need to test if something is true or false, use the ``if``
tag instead.
.. templatetag:: ifnotequal
ifnotequal
~~~~~~~~~~
Just like ``ifequal``, except it tests that the two arguments are not equal.
.. templatetag:: include
include
~~~~~~~
Loads a template and renders it with the current context. This is a way of
"including" other templates within a template.
The template name can either be a variable or a hard-coded (quoted) string,
in either single or double quotes.
This example includes the contents of the template ``"foo/bar.html"``::
{% include "foo/bar.html" %}
This example includes the contents of the template whose name is contained in
the variable ``template_name``::
{% include template_name %}
An included template is rendered with the context of the template that's
including it. This example produces the output ``"Hello, John"``:
* Context: variable ``person`` is set to ``"john"``.
* Template::
{% include "name_snippet.html" %}
* The ``name_snippet.html`` template::
Hello, {{ person }}
See also: ``{% ssi %}``.
.. templatetag:: load
load
~~~~
Load a custom template tag set.
See :ref:`Custom tag and filter libraries <howto-custom-template-tags>` for more information.
.. templatetag:: now
now
~~~
Display the date, formatted according to the given string.
Uses the same format as PHP's ``date()`` function (http://php.net/date)
with some custom extensions.
Available format strings:
================ ======================================== =====================
Format character Description Example output
================ ======================================== =====================
a ``'a.m.'`` or ``'p.m.'`` (Note that ``'a.m.'``
this is slightly different than PHP's
output, because this includes periods
to match Associated Press style.)
A ``'AM'`` or ``'PM'``. ``'AM'``
b Month, textual, 3 letters, lowercase. ``'jan'``
B Not implemented.
d Day of the month, 2 digits with ``'01'`` to ``'31'``
leading zeros.
D Day of the week, textual, 3 letters. ``'Fri'``
f Time, in 12-hour hours and minutes, ``'1'``, ``'1:30'``
with minutes left off if they're zero.
Proprietary extension.
F Month, textual, long. ``'January'``
g Hour, 12-hour format without leading ``'1'`` to ``'12'``
zeros.
G Hour, 24-hour format without leading ``'0'`` to ``'23'``
zeros.
h Hour, 12-hour format. ``'01'`` to ``'12'``
H Hour, 24-hour format. ``'00'`` to ``'23'``
i Minutes. ``'00'`` to ``'59'``
I Not implemented.
j Day of the month without leading ``'1'`` to ``'31'``
zeros.
l Day of the week, textual, long. ``'Friday'``
L Boolean for whether it's a leap year. ``True`` or ``False``
m Month, 2 digits with leading zeros. ``'01'`` to ``'12'``
M Month, textual, 3 letters. ``'Jan'``
n Month without leading zeros. ``'1'`` to ``'12'``
N Month abbreviation in Associated Press ``'Jan.'``, ``'Feb.'``, ``'March'``, ``'May'``
style. Proprietary extension.
O Difference to Greenwich time in hours. ``'+0200'``
P Time, in 12-hour hours, minutes and ``'1 a.m.'``, ``'1:30 p.m.'``, ``'midnight'``, ``'noon'``, ``'12:30 p.m.'``
'a.m.'/'p.m.', with minutes left off
if they're zero and the special-case
strings 'midnight' and 'noon' if
appropriate. Proprietary extension.
r RFC 2822 formatted date. ``'Thu, 21 Dec 2000 16:01:07 +0200'``
s Seconds, 2 digits with leading zeros. ``'00'`` to ``'59'``
S English ordinal suffix for day of the ``'st'``, ``'nd'``, ``'rd'`` or ``'th'``
month, 2 characters.
t Number of days in the given month. ``28`` to ``31``
T Time zone of this machine. ``'EST'``, ``'MDT'``
U Seconds since the Unix Epoch
(January 1 1970 00:00:00 UTC).
w Day of the week, digits without ``'0'`` (Sunday) to ``'6'`` (Saturday)
leading zeros.
W ISO-8601 week number of year, with ``1``, ``53``
weeks starting on Monday.
y Year, 2 digits. ``'99'``
Y Year, 4 digits. ``'1999'``
z Day of the year. ``0`` to ``365``
Z Time zone offset in seconds. The ``-43200`` to ``43200``
offset for timezones west of UTC is
always negative, and for those east of
UTC is always positive.
================ ======================================== =====================
Example::
It is {% now "jS F Y H:i" %}
Note that you can backslash-escape a format string if you want to use the
"raw" value. In this example, "f" is backslash-escaped, because otherwise
"f" is a format string that displays the time. The "o" doesn't need to be
escaped, because it's not a format character::
It is the {% now "jS o\f F" %}
This would display as "It is the 4th of September".
.. templatetag:: regroup
regroup
~~~~~~~
Regroup a list of alike objects by a common attribute.
This complex tag is best illustrated by use of an example: say that ``people``
is a list of people represented by dictionaries with ``first_name``,
``last_name``, and ``gender`` keys:
.. code-block:: python
people = [
{'first_name': 'George', 'last_name': 'Bush', 'gender': 'Male'},
{'first_name': 'Bill', 'last_name': 'Clinton', 'gender': 'Male'},
{'first_name': 'Margaret', 'last_name': 'Thatcher', 'gender': 'Female'},
{'first_name': 'Condoleezza', 'last_name': 'Rice', 'gender': 'Female'},
{'first_name': 'Pat', 'last_name': 'Smith', 'gender': 'Unknown'},
]
...and you'd like to display a hierarchical list that is ordered by gender,
like this:
* Male:
* George Bush
* Bill Clinton
* Female:
* Margaret Thatcher
* Condoleezza Rice
* Unknown:
* Pat Smith
You can use the ``{% regroup %}`` tag to group the list of people by gender.
The following snippet of template code would accomplish this::
{% regroup people by gender as gender_list %}
<ul>
{% for gender in gender_list %}
<li>{{ gender.grouper }}
<ul>
{% for item in gender.list %}
<li>{{ item.first_name }} {{ item.last_name }}</li>
{% endfor %}
</ul>
</li>
{% endfor %}
</ul>
Let's walk through this example. ``{% regroup %}`` takes three arguments: the
list you want to regroup, the attribute to group by, and the name of the
resulting list. Here, we're regrouping the ``people`` list by the ``gender``
attribute and calling the result ``gender_list``.
``{% regroup %}`` produces a list (in this case, ``gender_list``) of
**group objects**. Each group object has two attributes:
* ``grouper`` -- the item that was grouped by (e.g., the string "Male" or
"Female").
* ``list`` -- a list of all items in this group (e.g., a list of all people
with gender='Male').
Note that ``{% regroup %}`` does not order its input! Our example relies on
the fact that the ``people`` list was ordered by ``gender`` in the first place.
If the ``people`` list did *not* order its members by ``gender``, the regrouping
would naively display more than one group for a single gender. For example,
say the ``people`` list was set to this (note that the males are not grouped
together):
.. code-block:: python
people = [
{'first_name': 'Bill', 'last_name': 'Clinton', 'gender': 'Male'},
{'first_name': 'Pat', 'last_name': 'Smith', 'gender': 'Unknown'},
{'first_name': 'Margaret', 'last_name': 'Thatcher', 'gender': 'Female'},
{'first_name': 'George', 'last_name': 'Bush', 'gender': 'Male'},
{'first_name': 'Condoleezza', 'last_name': 'Rice', 'gender': 'Female'},
]
With this input for ``people``, the example ``{% regroup %}`` template code
above would result in the following output:
* Male:
* Bill Clinton
* Unknown:
* Pat Smith
* Female:
* Margaret Thatcher
* Male:
* George Bush
* Female:
* Condoleezza Rice
The easiest solution to this gotcha is to make sure in your view code that the
data is ordered according to how you want to display it.
Another solution is to sort the data in the template using the ``dictsort``
filter, if your data is in a list of dictionaries::
{% regroup people|dictsort:"gender" by gender as gender_list %}
.. templatetag:: spaceless
spaceless
~~~~~~~~~
Removes whitespace between HTML tags. This includes tab
characters and newlines.
Example usage::
{% spaceless %}
<p>
<a href="foo/">Foo</a>
</p>
{% endspaceless %}
This example would return this HTML::
<p><a href="foo/">Foo</a></p>
Only space between *tags* is removed -- not space between tags and text. In
this example, the space around ``Hello`` won't be stripped::
{% spaceless %}
<strong>
Hello
</strong>
{% endspaceless %}
.. templatetag:: ssi
ssi
~~~
Output the contents of a given file into the page.
Like a simple "include" tag, ``{% ssi %}`` includes the contents of another
file -- which must be specified using an absolute path -- in the current
page::
{% ssi /home/html/ljworld.com/includes/right_generic.html %}
If the optional "parsed" parameter is given, the contents of the included
file are evaluated as template code, within the current context::
{% ssi /home/html/ljworld.com/includes/right_generic.html parsed %}
Note that if you use ``{% ssi %}``, you'll need to define
:setting:`ALLOWED_INCLUDE_ROOTS` in your Django settings, as a security measure.
See also: ``{% include %}``.
.. templatetag:: templatetag
templatetag
~~~~~~~~~~~
Output one of the syntax characters used to compose template tags.
Since the template system has no concept of "escaping", to display one of the
bits used in template tags, you must use the ``{% templatetag %}`` tag.
The argument tells which template bit to output:
================== =======
Argument Outputs
================== =======
``openblock`` ``{%``
``closeblock`` ``%}``
``openvariable`` ``{{``
``closevariable`` ``}}``
``openbrace`` ``{``
``closebrace`` ``}``
``opencomment`` ``{#``
``closecomment`` ``#}``
================== =======
.. templatetag:: url
url
~~~
Returns an absolute URL (i.e., a URL without the domain name) matching a given
view function and optional parameters. This is a way to output links without
violating the DRY principle by having to hard-code URLs in your templates::
{% url path.to.some_view v1,v2 %}
The first argument is a path to a view function in the format
``package.package.module.function``. Additional arguments are optional and
should be comma-separated values that will be used as arguments in the URL.
The example above shows passing positional arguments. Alternatively you may
use keyword syntax::
{% url path.to.some_view arg1=v1,arg2=v2 %}
Do not mix both positional and keyword syntax in a single call. All arguments
required by the URLconf should be present.
For example, suppose you have a view, ``app_views.client``, whose URLconf
takes a client ID (here, ``client()`` is a method inside the views file
``app_views.py``). The URLconf line might look like this:
.. code-block:: python
('^client/(\d+)/$', 'app_views.client')
If this app's URLconf is included into the project's URLconf under a path
such as this:
.. code-block:: python
('^clients/', include('project_name.app_name.urls'))
...then, in a template, you can create a link to this view like this::
{% url app_views.client client.id %}
The template tag will output the string ``/clients/client/123/``.
.. versionadded:: 1.0
If you're using :ref:`named URL patterns <naming-url-patterns>`, you can
refer to the name of the pattern in the ``url`` tag instead of using the
path to the view.
Note that if the URL you're reversing doesn't exist, you'll get an
:exc:`NoReverseMatch` exception raised, which will cause your site to display an
error page.
.. versionadded:: 1.0
If you'd like to retrieve a URL without displaying it, you can use a slightly
different call::
{% url path.to.view arg, arg2 as the_url %}
<a href="{{ the_url }}">I'm linking to {{ the_url }}</a>
This ``{% url ... as var %}`` syntax will *not* cause an error if the view is
missing. In practice you'll use this to link to views that are optional::
{% url path.to.view as the_url %}
{% if the_url %}
<a href="{{ the_url }}">Link to optional stuff</a>
{% endif %}
.. versionadded:: 1.1
If you'd like to retrieve a namespaced URL, specify the fully qualified name::
{% url myapp:view-name %}
This will follow the normal :ref:`namespaced URL resolution strategy
<topics-http-reversing-url-namespaces>`, including using any hints provided
by the context as to the current application.
.. templatetag:: widthratio
widthratio
~~~~~~~~~~
For creating bar charts and such, this tag calculates the ratio of a given value
to a maximum value, and then applies that ratio to a constant.
For example::
<img src="bar.gif" height="10" width="{% widthratio this_value max_value 100 %}" />
Above, if ``this_value`` is 175 and ``max_value`` is 200, the image in the
above example will be 88 pixels wide (because 175/200 = .875; .875 * 100 = 87.5
which is rounded up to 88).
.. templatetag:: with
with
~~~~
.. versionadded:: 1.0
Caches a complex variable under a simpler name. This is useful when accessing
an "expensive" method (e.g., one that hits the database) multiple times.
For example::
{% with business.employees.count as total %}
{{ total }} employee{{ total|pluralize }}
{% endwith %}
The populated variable (in the example above, ``total``) is only available
between the ``{% with %}`` and ``{% endwith %}`` tags.
.. _ref-templates-builtins-filters:
Built-in filter reference
-------------------------
.. templatefilter:: add
add
~~~
Adds the argument to the value.
For example::
{{ value|add:"2" }}
If ``value`` is ``4``, then the output will be ``6``.
.. templatefilter:: addslashes
addslashes
~~~~~~~~~~
Adds slashes before quotes. Useful for escaping strings in CSV, for example.
For example::
{{ value|addslashes }}
If ``value`` is ``"I'm using Django"``, the output will be ``"I\'m using Django"``.
.. templatefilter:: capfirst
capfirst
~~~~~~~~
Capitalizes the first character of the value.
For example::
{{ value|capfirst }}
If ``value`` is ``"django"``, the output will be ``"Django"``.
.. templatefilter:: center
center
~~~~~~
Centers the value in a field of a given width.
For example::
"{{ value|center:"15" }}"
If ``value`` is ``"Django"``, the output will be ``" Django "``.
.. templatefilter:: cut
cut
~~~
Removes all values of arg from the given string.
For example::
{{ value|cut:" "}}
If ``value`` is ``"String with spaces"``, the output will be ``"Stringwithspaces"``.
.. templatefilter:: date
date
~~~~
Formats a date according to the given format (same as the `now`_ tag).
For example::
{{ value|date:"D d M Y" }}
If ``value`` is a ``datetime`` object (e.g., the result of
``datetime.datetime.now()``), the output will be the string
``'Wed 09 Jan 2008'``.
When used without a format string::
{{ value|date }}
...the formatting string defined in the :setting:`DATE_FORMAT` setting will be
used.
.. templatefilter:: default
default
~~~~~~~
If value evaluates to ``False``, use given default. Otherwise, use the value.
For example::
{{ value|default:"nothing" }}
If ``value`` is ``""`` (the empty string), the output will be ``nothing``.
.. templatefilter:: default_if_none
default_if_none
~~~~~~~~~~~~~~~
If (and only if) value is ``None``, use given default. Otherwise, use the
value.
Note that if an empty string is given, the default value will *not* be used.
Use the ``default`` filter if you want to fallback for empty strings.
For example::
{{ value|default_if_none:"nothing" }}
If ``value`` is ``None``, the output will be the string ``"nothing"``.
.. templatefilter:: dictsort
dictsort
~~~~~~~~
Takes a list of dictionaries and returns that list sorted by the key given in
the argument.
For example::
{{ value|dictsort:"name" }}