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builtins.txt
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==================================
Built-in template tags and filters
==================================
This document describes Django's built-in template tags and filters. It is
recommended that you use the :doc:`automatic documentation
</ref/contrib/admin/admindocs>`, 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
^^^^^^^^^^
Controls 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. The block is closed with an ``endautoescape`` ending tag.
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 :tfilter:`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 :tfilter:`safe` or :tfilter:`escape` filters applied.
Sample usage::
{% autoescape on %}
{{ body }}
{% endautoescape %}
.. templatetag:: block
block
^^^^^
Defines a block that can be overridden by child templates. See
:ref:`Template inheritance <template-inheritance>` for more information.
.. templatetag:: comment
comment
^^^^^^^
Ignores everything between ``{% comment %}`` and ``{% endcomment %}``.
Sample usage::
<p>Rendered text with {{ pub_date|date:"c" }}</p>
{% comment %}
<p>Commented out text with {{ create_date|date:"c" }}</p>
{% endcomment %}
``comment`` tags cannot be nested.
.. templatetag:: csrf_token
csrf_token
^^^^^^^^^^
This tag is used for CSRF protection, as described in the documentation for
:doc:`Cross Site Request Forgeries </ref/contrib/csrf>`.
.. templatetag:: cycle
cycle
^^^^^
Produces one of its arguments each time this tag is encountered. The first
argument is produced on the first encounter, the second argument on the second
encounter, and so forth. Once all arguments are exhausted, the tag cycles to
the first argument and produces it again.
This tag is particularly useful in a loop::
{% for o in some_list %}
<tr class="{% cycle 'row1' 'row2' %}">
...
</tr>
{% endfor %}
The first iteration produces HTML that refers to class ``row1``, the second to
``row2``, the third to ``row1`` again, and so on for each iteration of the
loop.
You can use variables, too. For example, if you have two template variables,
``rowvalue1`` and ``rowvalue2``, you can alternate between their values like
this::
{% for o in some_list %}
<tr class="{% cycle rowvalue1 rowvalue2 %}">
...
</tr>
{% endfor %}
Note that the variables included in the cycle will not be escaped. Any HTML or
Javascript code contained in the printed variable will be rendered as-is, which
could potentially lead to security issues. So either make sure that you trust
their values or use explicit escaping like this::
{% for o in some_list %}
<tr class="{% filter force_escape %}{% cycle rowvalue1 rowvalue2 %}{% endfilter %}">
...
</tr>
{% endfor %}
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 current value of a cycle
without advancing to the next value. 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 by referencing the cycle name as a context variable. If you
want to move the cycle to the next value independently of the original
``cycle`` tag, you can use another ``cycle`` tag and specify the name of the
variable. So, the following template::
<tr>
<td class="{% cycle 'row1' 'row2' as rowcolors %}">...</td>
<td class="{{ rowcolors }}">...</td>
</tr>
<tr>
<td class="{% cycle rowcolors %}">...</td>
<td class="{{ rowcolors }}">...</td>
</tr>
would output::
<tr>
<td class="row1">...</td>
<td class="row1">...</td>
</tr>
<tr>
<td class="row2">...</td>
<td class="row2">...</td>
</tr>
You can use any number of values in a ``cycle`` tag, separated by spaces.
Values enclosed in single quotes (``'``) or double quotes (``"``) are treated
as string literals, while values without quotes are treated as template
variables.
By default, when you use the ``as`` keyword with the cycle tag, the
usage of ``{% cycle %}`` that initiates the cycle will itself produce
the first value in the cycle. This could be a problem if you want to
use the value in a nested loop or an included template. If you only want
to declare the cycle but not produce the first value, you can add a
``silent`` keyword as the last keyword in the tag. For example::
{% for obj in some_list %}
{% cycle 'row1' 'row2' as rowcolors silent %}
<tr class="{{ rowcolors }}">{% include "subtemplate.html" %}</tr>
{% endfor %}
This will output a list of ``<tr>`` elements with ``class``
alternating between ``row1`` and ``row2``. The subtemplate will have
access to ``rowcolors`` in its context and the value will match the class
of the ``<tr>`` that encloses it. If the ``silent`` keyword were to be
omitted, ``row1`` and ``row2`` would be emitted as normal text, outside the
``<tr>`` element.
When the silent keyword is used on a cycle definition, the silence
automatically applies to all subsequent uses of that specific cycle tag.
The following template would output *nothing*, even though the second
call to ``{% cycle %}`` doesn't specify ``silent``::
{% cycle 'row1' 'row2' as rowcolors silent %}
{% cycle rowcolors %}
For backward 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?
.. versionchanged:: 1.6
To improve safety, future versions of ``cycle`` will automatically escape
their output. You're encouraged to activate this behavior by loading
``cycle`` from the ``future`` template library::
{% load cycle from future %}
When using the ``future`` version, you can disable auto-escaping with::
{% for o in some_list %}
<tr class="{% autoescape off %}{% cycle rowvalue1 rowvalue2 %}{% endautoescape %}">
...
</tr>
{% endfor %}
.. templatetag:: debug
debug
^^^^^
Outputs a whole load of debugging information, including the current context
and imported modules.
.. templatetag:: extends
extends
^^^^^^^
Signals 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
^^^^^^
Filters the contents of the block through one or more filters. Multiple
filters can be specified with pipes and filters can have arguments, just as
in variable syntax.
Note that the block includes *all* the text between the ``filter`` and
``endfilter`` tags.
Sample usage::
{% filter force_escape|lower %}
This text will be HTML-escaped, and will appear in all lowercase.
{% endfilter %}
.. note::
The :tfilter:`escape` and :tfilter:`safe` filters are not acceptable
arguments. Instead, use the :ttag:`autoescape` tag to manage autoescaping
for blocks of template code.
.. templatetag:: firstof
firstof
^^^^^^^
Outputs the first argument variable that is not False. This tag does *not*
auto-escape variable values.
Outputs nothing if all the passed variables are False.
Sample usage::
{% firstof var1 var2 var3 %}
This is equivalent to::
{% if var1 %}
{{ var1|safe }}
{% elif var2 %}
{{ var2|safe }}
{% elif var3 %}
{{ var3|safe }}
{% 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 currently the variables included in the firstof tag will not be
escaped. 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 %}
.. versionchanged:: 1.6
To improve safety, future versions of ``firstof`` will automatically escape
their output. You're encouraged to activate this behavior by loading
``firstof`` from the ``future`` template library::
{% load firstof from future %}
When using the ``future`` version, you can disable auto-escaping with::
{% autoescape off %}
{% firstof var1 var2 var3 "<strong>fallback value</strong>" %}
{% endautoescape %}
Or if only some variables should be escaped, you can use::
{% firstof var1 var2|safe var3 "<strong>fallback value</strong>"|safe %}
.. templatetag:: for
for
^^^
Loops over each item in an array, making the item available in a context
variable. 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 %}``.
If you need to loop over a list of lists, you can unpack the values
in each sublist 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 surrounding
the current one
========================== ===============================================
for ... empty
^^^^^^^^^^^^^
The ``for`` tag can take an optional ``{% empty %}`` clause whose text is
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 athletes 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 }}
{% elif athlete_in_locker_room_list %}
Athletes should be out of the locker room soon!
{% 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 may take one or several ``{% elif %}``
clauses, as well as an ``{% else %}`` clause that will be displayed if all
previous conditions fail. These clauses are optional.
Boolean operators
^^^^^^^^^^^^^^^^^
:ttag:`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 %}
Use of both ``and`` and ``or`` clauses within the same tag is allowed, with
``and`` having higher precedence than ``or`` e.g.::
{% if athlete_list and coach_list or cheerleader_list %}
will be interpreted like:
.. code-block:: python
if (athlete_list and coach_list) or cheerleader_list
Use of actual parentheses in the :ttag:`if` tag is invalid syntax. If you need
them to indicate precedence, you should use nested :ttag:`if` tags.
:ttag:`if` tags may also use the operators ``==``, ``!=``, ``<``, ``>``,
``<=``, ``>=`` and ``in`` which work as follows:
``==`` operator
^^^^^^^^^^^^^^^
Equality. Example::
{% if somevar == "x" %}
This appears if variable somevar equals the string "x"
{% endif %}
``!=`` operator
^^^^^^^^^^^^^^^
Inequality. Example::
{% if somevar != "x" %}
This appears if variable somevar does not equal the string "x",
or if somevar is not found in the context
{% endif %}
``<`` operator
^^^^^^^^^^^^^^
Less than. Example::
{% if somevar < 100 %}
This appears if variable somevar is less than 100.
{% endif %}
``>`` operator
^^^^^^^^^^^^^^
Greater than. Example::
{% if somevar > 0 %}
This appears if variable somevar is greater than 0.
{% endif %}
``<=`` operator
^^^^^^^^^^^^^^^
Less than or equal to. Example::
{% if somevar <= 100 %}
This appears if variable somevar is less than 100 or equal to 100.
{% endif %}
``>=`` operator
^^^^^^^^^^^^^^^
Greater than or equal to. Example::
{% if somevar >= 1 %}
This appears if variable somevar is greater than 1 or equal to 1.
{% endif %}
``in`` operator
^^^^^^^^^^^^^^^
Contained within. This operator is supported by many Python containers to test
whether the given value is in the container. The following are some examples
of how ``x in y`` will be interpreted::
{% if "bc" in "abcdef" %}
This appears since "bc" is a substring of "abcdef"
{% endif %}
{% if "hello" in greetings %}
If greetings is a list or set, one element of which is the string
"hello", this will appear.
{% endif %}
{% if user in users %}
If users is a QuerySet, this will appear if user is an
instance that belongs to the QuerySet.
{% endif %}
``not in`` operator
^^^^^^^^^^^^^^^^^^^
Not contained within. This is the negation of the ``in`` operator.
The comparison operators cannot be 'chained' like in Python or in mathematical
notation. For example, instead of using::
{% if a > b > c %} (WRONG)
you should use::
{% if a > b and b > c %}
Filters
^^^^^^^
You can also use filters in the :ttag:`if` expression. For example::
{% if messages|length >= 100 %}
You have lots of messages today!
{% endif %}
Complex expressions
^^^^^^^^^^^^^^^^^^^
All of the above can be combined to form complex expressions. For such
expressions, it can be important to know how the operators are grouped when the
expression is evaluated - that is, the precedence rules. The precedence of the
operators, from lowest to highest, is as follows:
* ``or``
* ``and``
* ``not``
* ``in``
* ``==``, ``!=``, ``<``, ``>``, ``<=``, ``>=``
(This follows Python exactly). So, for example, the following complex
:ttag:`if` tag:
.. code-block:: django
{% if a == b or c == d and e %}
...will be interpreted as:
.. code-block:: python
(a == b) or ((c == d) and e)
If you need different precedence, you will need to use nested :ttag:`if` tags.
Sometimes that is better for clarity anyway, for the sake of those who do not
know the precedence rules.
.. 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 one or more variables, check whether any variable has changed.
For example, the following shows the date every time it changes, while
showing the hour if either the hour or 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.pk comment.user_id %}
...
{% endifequal %}
As in the :ttag:`if` tag, an ``{% else %}`` clause is optional.
The arguments can be hard-coded strings, so the following is valid::
{% ifequal user.username "adrian" %}
...
{% endifequal %}
An alternative to the ``ifequal`` tag is to use the :ttag:`if` tag and the
``==`` operator.
.. templatetag:: ifnotequal
ifnotequal
^^^^^^^^^^
Just like :ttag:`ifequal`, except it tests that the two arguments are not
equal.
An alternative to the ``ifnotequal`` tag is to use the :ttag:`if` tag and
the ``!=`` operator.
.. 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 within the context of the template that
includes 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::
{{ greeting }}, {{ person|default:"friend" }}!
You can pass additional context to the template using keyword arguments::
{% include "name_snippet.html" with person="Jane" greeting="Hello" %}
If you want to render the context only with the variables provided (or even
no variables at all), use the ``only`` option. No other variables are
available to the included template::
{% include "name_snippet.html" with greeting="Hi" only %}
.. note::
The :ttag:`include` tag should be considered as an implementation of
"render this subtemplate and include the HTML", not as "parse this
subtemplate and include its contents as if it were part of the parent".
This means that there is no shared state between included templates --
each include is a completely independent rendering process.
See also: :ttag:`{% ssi %}<ssi>`.
.. templatetag:: load
load
^^^^
Loads a custom template tag set.
For example, the following template would load all the tags and filters
registered in ``somelibrary`` and ``otherlibrary`` located in package
``package``::
{% load somelibrary package.otherlibrary %}
You can also selectively load individual filters or tags from a library, using
the ``from`` argument. In this example, the template tags/filters named ``foo``
and ``bar`` will be loaded from ``somelibrary``::
{% load foo bar from somelibrary %}
See :doc:`Custom tag and filter libraries </howto/custom-template-tags>` for
more information.
.. templatetag:: now
now
^^^
Displays the current date and/or time, using a format according to the given
string. Such string can contain format specifiers characters as described
in the :tfilter:`date` filter section.
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".
.. note::
The format passed can also be one of the predefined ones
:setting:`DATE_FORMAT`, :setting:`DATETIME_FORMAT`,
:setting:`SHORT_DATE_FORMAT` or :setting:`SHORT_DATETIME_FORMAT`.
The predefined formats may vary depending on the current locale and
if :ref:`format-localization` is enabled, e.g.::
It is {% now "SHORT_DATETIME_FORMAT" %}
.. templatetag:: regroup
regroup
^^^^^^^
Regroups a list of alike objects by a common attribute.
This complex tag is best illustrated by way of an example: say that "places" is a list of cities represented by dictionaries containing ``"name"``, ``"population"``, and ``"country"`` keys:
.. code-block:: python
cities = [
{'name': 'Mumbai', 'population': '19,000,000', 'country': 'India'},
{'name': 'Calcutta', 'population': '15,000,000', 'country': 'India'},
{'name': 'New York', 'population': '20,000,000', 'country': 'USA'},
{'name': 'Chicago', 'population': '7,000,000', 'country': 'USA'},
{'name': 'Tokyo', 'population': '33,000,000', 'country': 'Japan'},
]
...and you'd like to display a hierarchical list that is ordered by country, like this:
* India
* Mumbai: 19,000,000
* Calcutta: 15,000,000
* USA
* New York: 20,000,000
* Chicago: 7,000,000
* Japan
* Tokyo: 33,000,000
You can use the ``{% regroup %}`` tag to group the list of cities by country.
The following snippet of template code would accomplish this::
{% regroup cities by country as country_list %}
<ul>
{% for country in country_list %}
<li>{{ country.grouper }}
<ul>
{% for item in country.list %}
<li>{{ item.name }}: {{ item.population }}</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 ``cities`` list by the ``country``
attribute and calling the result ``country_list``.
``{% regroup %}`` produces a list (in this case, ``country_list``) of
**group objects**. Each group object has two attributes:
* ``grouper`` -- the item that was grouped by (e.g., the string "India" or
"Japan").
* ``list`` -- a list of all items in this group (e.g., a list of all cities
with country='India').
Note that ``{% regroup %}`` does not order its input! Our example relies on
the fact that the ``cities`` list was ordered by ``country`` in the first place.
If the ``cities`` list did *not* order its members by ``country``, the
regrouping would naively display more than one group for a single country. For
example, say the ``cities`` list was set to this (note that the countries are not
grouped together):
.. code-block:: python
cities = [
{'name': 'Mumbai', 'population': '19,000,000', 'country': 'India'},
{'name': 'New York', 'population': '20,000,000', 'country': 'USA'},
{'name': 'Calcutta', 'population': '15,000,000', 'country': 'India'},
{'name': 'Chicago', 'population': '7,000,000', 'country': 'USA'},
{'name': 'Tokyo', 'population': '33,000,000', 'country': 'Japan'},
]
With this input for ``cities``, the example ``{% regroup %}`` template code
above would result in the following output:
* India
* Mumbai: 19,000,000
* USA
* New York: 20,000,000
* India
* Calcutta: 15,000,000
* USA
* Chicago: 7,000,000
* Japan
* Tokyo: 33,000,000
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
:tfilter:`dictsort` filter, if your data is in a list of dictionaries::
{% regroup cities|dictsort:"country" by country as country_list %}
Grouping on other properties
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Any valid template lookup is a legal grouping attribute for the regroup
tag, including methods, attributes, dictionary keys and list items. For
example, if the "country" field is a foreign key to a class with
an attribute "description," you could use::
{% regroup cities by country.description as country_list %}
Or, if ``country`` is a field with ``choices``, it will have a
:meth:`~django.db.models.Model.get_FOO_display` method available as an
attribute, allowing you to group on the display string rather than the
``choices`` key::
{% regroup cities by get_country_display as country_list %}
``{{ country.grouper }}`` will now display the value fields from the
``choices`` set rather than the keys.
.. 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
^^^
Outputs the contents of a given file into the page.
Like a simple :ttag:`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' %}
The first parameter of ``ssi`` can be a quoted literal or any other context
variable.
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: :ttag:`{% include %}<include>`.
.. templatetag:: templatetag
templatetag
^^^^^^^^^^^
Outputs 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`` ``#}``
================== =======
Sample usage::
{% templatetag openblock %} url 'entry_list' {% templatetag closeblock %}
.. templatetag:: url
url
^^^
Returns an absolute path reference (a URL without the domain name) matching a
given view function and optional parameters.