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  <div class="section" id="s-internationalization">
<span id="internationalization"></span><h1>Internationalization<a class="headerlink" href="#internationalization" title="Permalink to this headline">¶</a></h1>
<div class="section" id="s-overview">
<span id="overview"></span><h2>Overview<a class="headerlink" href="#overview" title="Permalink to this headline">¶</a></h2>
<p>The goal of internationalization is to allow a single Web application to offer
its content and functionality in multiple languages and locales.</p>
<p>For text translations, you, the Django developer, can accomplish this goal by
adding a minimal amount of hooks to your Python and templates. These hooks
are called <strong>translation strings</strong>. They tell Django: &#8220;This text should be
translated into the end user&#8217;s language, if a translation for this text is
available in that language.&#8221; It&#8217;s your responsibility to mark translatable
strings; the system can only translate strings it knows about.</p>
<p>Django takes care of using these hooks to translate Web apps, on the fly,
according to users&#8217; language preferences.</p>
</div>
<div class="section" id="s-specifying-translation-strings-in-python-code">
<span id="specifying-translation-strings-in-python-code"></span><h2>Specifying translation strings: In Python code<a class="headerlink" href="#specifying-translation-strings-in-python-code" title="Permalink to this headline">¶</a></h2>
<div class="section" id="s-standard-translation">
<span id="standard-translation"></span><h3>Standard translation<a class="headerlink" href="#standard-translation" title="Permalink to this headline">¶</a></h3>
<p>Specify a translation string by using the function <tt class="docutils literal"><span class="pre">ugettext()</span></tt>. It&#8217;s
convention to import this as a shorter alias, <tt class="docutils literal"><span class="pre">_</span></tt>, to save typing.</p>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p>Python&#8217;s standard library <tt class="docutils literal"><span class="pre">gettext</span></tt> module installs <tt class="docutils literal"><span class="pre">_()</span></tt> into the
global namespace, as an alias for <tt class="docutils literal"><span class="pre">gettext()</span></tt>. In Django, we have chosen
not to follow this practice, for a couple of reasons:</p>
<ol class="last arabic simple">
<li>For international character set (Unicode) support, <tt class="docutils literal"><span class="pre">ugettext()</span></tt> is
more useful than <tt class="docutils literal"><span class="pre">gettext()</span></tt>. Sometimes, you should be using
<tt class="docutils literal"><span class="pre">ugettext_lazy()</span></tt> as the default translation method for a particular
file. Without <tt class="docutils literal"><span class="pre">_()</span></tt> in the global namespace, the developer has to
think about which is the most appropriate translation function.</li>
<li>The underscore character (<tt class="docutils literal"><span class="pre">_</span></tt>) is used to represent &#8220;the previous
result&#8221; in Python&#8217;s interactive shell and doctest tests. Installing a
global <tt class="docutils literal"><span class="pre">_()</span></tt> function causes interference. Explicitly importing
<tt class="docutils literal"><span class="pre">ugettext()</span></tt> as <tt class="docutils literal"><span class="pre">_()</span></tt> avoids this problem.</li>
</ol>
</div>
<p>In this example, the text <tt class="docutils literal"><span class="pre">&quot;Welcome</span> <span class="pre">to</span> <span class="pre">my</span> <span class="pre">site.&quot;</span></tt> is marked as a translation
string:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">django.utils.translation</span> <span class="kn">import</span> <span class="n">ugettext</span> <span class="k">as</span> <span class="n">_</span>

<span class="k">def</span> <span class="nf">my_view</span><span class="p">(</span><span class="n">request</span><span class="p">):</span>
    <span class="n">output</span> <span class="o">=</span> <span class="n">_</span><span class="p">(</span><span class="s">&quot;Welcome to my site.&quot;</span><span class="p">)</span>
    <span class="k">return</span> <span class="n">HttpResponse</span><span class="p">(</span><span class="n">output</span><span class="p">)</span>
</pre></div>
</div>
<p>Obviously, you could code this without using the alias. This example is
identical to the previous one:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">django.utils.translation</span> <span class="kn">import</span> <span class="n">ugettext</span>

<span class="k">def</span> <span class="nf">my_view</span><span class="p">(</span><span class="n">request</span><span class="p">):</span>
    <span class="n">output</span> <span class="o">=</span> <span class="n">ugettext</span><span class="p">(</span><span class="s">&quot;Welcome to my site.&quot;</span><span class="p">)</span>
    <span class="k">return</span> <span class="n">HttpResponse</span><span class="p">(</span><span class="n">output</span><span class="p">)</span>
</pre></div>
</div>
<p>Translation works on computed values. This example is identical to the previous
two:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="k">def</span> <span class="nf">my_view</span><span class="p">(</span><span class="n">request</span><span class="p">):</span>
    <span class="n">words</span> <span class="o">=</span> <span class="p">[</span><span class="s">&#39;Welcome&#39;</span><span class="p">,</span> <span class="s">&#39;to&#39;</span><span class="p">,</span> <span class="s">&#39;my&#39;</span><span class="p">,</span> <span class="s">&#39;site.&#39;</span><span class="p">]</span>
    <span class="n">output</span> <span class="o">=</span> <span class="n">_</span><span class="p">(</span><span class="s">&#39; &#39;</span><span class="o">.</span><span class="n">join</span><span class="p">(</span><span class="n">words</span><span class="p">))</span>
    <span class="k">return</span> <span class="n">HttpResponse</span><span class="p">(</span><span class="n">output</span><span class="p">)</span>
</pre></div>
</div>
<p>Translation works on variables. Again, here's an identical example:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="k">def</span> <span class="nf">my_view</span><span class="p">(</span><span class="n">request</span><span class="p">):</span>
    <span class="n">sentence</span> <span class="o">=</span> <span class="s">&#39;Welcome to my site.&#39;</span>
    <span class="n">output</span> <span class="o">=</span> <span class="n">_</span><span class="p">(</span><span class="n">sentence</span><span class="p">)</span>
    <span class="k">return</span> <span class="n">HttpResponse</span><span class="p">(</span><span class="n">output</span><span class="p">)</span>
</pre></div>
</div>
<p>(The caveat with using variables or computed values, as in the previous two
examples, is that Django's translation-string-detecting utility,
<tt class="docutils literal"><span class="pre">django-admin.py</span> <span class="pre">makemessages</span></tt>, won't be able to find these strings. More on
<tt class="docutils literal"><span class="pre">makemessages</span></tt> later.)</p>
<p>The strings you pass to <tt class="docutils literal"><span class="pre">_()</span></tt> or <tt class="docutils literal"><span class="pre">ugettext()</span></tt> can take placeholders,
specified with Python's standard named-string interpolation syntax. Example:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="k">def</span> <span class="nf">my_view</span><span class="p">(</span><span class="n">request</span><span class="p">,</span> <span class="n">m</span><span class="p">,</span> <span class="n">d</span><span class="p">):</span>
    <span class="n">output</span> <span class="o">=</span> <span class="n">_</span><span class="p">(</span><span class="s">&#39;Today is </span><span class="si">%(month)s</span><span class="s">, </span><span class="si">%(day)s</span><span class="s">.&#39;</span><span class="p">)</span> <span class="o">%</span> <span class="p">{</span><span class="s">&#39;month&#39;</span><span class="p">:</span> <span class="n">m</span><span class="p">,</span> <span class="s">&#39;day&#39;</span><span class="p">:</span> <span class="n">d</span><span class="p">}</span>
    <span class="k">return</span> <span class="n">HttpResponse</span><span class="p">(</span><span class="n">output</span><span class="p">)</span>
</pre></div>
</div>
<p>This technique lets language-specific translations reorder the placeholder
text. For example, an English translation may be <tt class="docutils literal"><span class="pre">&quot;Today</span> <span class="pre">is</span> <span class="pre">November,</span> <span class="pre">26.&quot;</span></tt>,
while a Spanish translation may be <tt class="docutils literal"><span class="pre">&quot;Hoy</span> <span class="pre">es</span> <span class="pre">26</span> <span class="pre">de</span> <span class="pre">Noviembre.&quot;</span></tt> -- with the
placeholders (the month and the day) with their positions swapped.</p>
<p>For this reason, you should use named-string interpolation (e.g., <tt class="docutils literal"><span class="pre">%(day)s</span></tt>)
instead of positional interpolation (e.g., <tt class="docutils literal"><span class="pre">%s</span></tt> or <tt class="docutils literal"><span class="pre">%d</span></tt>) whenever you
have more than a single parameter. If you used positional interpolation,
translations wouldn't be able to reorder placeholder text.</p>
</div>
<div class="section" id="s-marking-strings-as-no-op">
<span id="marking-strings-as-no-op"></span><h3>Marking strings as no-op<a class="headerlink" href="#marking-strings-as-no-op" title="Permalink to this headline">¶</a></h3>
<p>Use the function <tt class="docutils literal"><span class="pre">django.utils.translation.ugettext_noop()</span></tt> to mark a string
as a translation string without translating it. The string is later translated
from a variable.</p>
<p>Use this if you have constant strings that should be stored in the source
language because they are exchanged over systems or users -- such as strings in
a database -- but should be translated at the last possible point in time, such
as when the string is presented to the user.</p>
</div>
<div class="section" id="s-pluralization">
<span id="pluralization"></span><h3>Pluralization<a class="headerlink" href="#pluralization" title="Permalink to this headline">¶</a></h3>
<p>Use the function <tt class="docutils literal"><span class="pre">django.utils.translation.ungettext()</span></tt> to specify pluralized
messages.</p>
<p><tt class="docutils literal"><span class="pre">ungettext</span></tt> takes three arguments: the singular translation string, the plural
translation string and the number of objects.</p>
<p>This function is useful when you need your Django application to be localizable
to languages where the number and complexity of <a class="reference external" href="http://www.gnu.org/software/gettext/manual/gettext.html#Plural-forms">plural forms</a> is
greater than the two forms used in English ('object' for the singular and
'objects' for all the cases where <tt class="docutils literal"><span class="pre">count</span></tt> is different from zero, irrespective
of its value.)</p>
<p>For example:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">django.utils.translation</span> <span class="kn">import</span> <span class="n">ungettext</span>
<span class="k">def</span> <span class="nf">hello_world</span><span class="p">(</span><span class="n">request</span><span class="p">,</span> <span class="n">count</span><span class="p">):</span>
    <span class="n">page</span> <span class="o">=</span> <span class="n">ungettext</span><span class="p">(</span><span class="s">&#39;there is </span><span class="si">%(count)d</span><span class="s"> object&#39;</span><span class="p">,</span> <span class="s">&#39;there are </span><span class="si">%(count)d</span><span class="s"> objects&#39;</span><span class="p">,</span> <span class="n">count</span><span class="p">)</span> <span class="o">%</span> <span class="p">{</span>
        <span class="s">&#39;count&#39;</span><span class="p">:</span> <span class="n">count</span><span class="p">,</span>
    <span class="p">}</span>
    <span class="k">return</span> <span class="n">HttpResponse</span><span class="p">(</span><span class="n">page</span><span class="p">)</span>
</pre></div>
</div>
<p>In this example the number of objects is passed to the translation languages as
the <tt class="docutils literal"><span class="pre">count</span></tt> variable.</p>
<p>Lets see a slightly more complex usage example:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">django.utils.translation</span> <span class="kn">import</span> <span class="n">ungettext</span>

<span class="n">count</span> <span class="o">=</span> <span class="n">Report</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">count</span><span class="p">()</span>
<span class="k">if</span> <span class="n">count</span> <span class="o">==</span> <span class="mi">1</span><span class="p">:</span>
    <span class="n">name</span> <span class="o">=</span> <span class="n">Report</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">verbose_name</span>
<span class="k">else</span><span class="p">:</span>
    <span class="n">name</span> <span class="o">=</span> <span class="n">Report</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">verbose_name_plural</span>

<span class="n">text</span> <span class="o">=</span> <span class="n">ungettext</span><span class="p">(</span>
        <span class="s">&#39;There is </span><span class="si">%(count)d</span><span class="s"> </span><span class="si">%(name)s</span><span class="s"> available.&#39;</span><span class="p">,</span>
        <span class="s">&#39;There are </span><span class="si">%(count)d</span><span class="s"> </span><span class="si">%(name)s</span><span class="s"> available.&#39;</span><span class="p">,</span>
        <span class="n">count</span>
<span class="p">)</span> <span class="o">%</span> <span class="p">{</span>
    <span class="s">&#39;count&#39;</span><span class="p">:</span> <span class="n">count</span><span class="p">,</span>
    <span class="s">&#39;name&#39;</span><span class="p">:</span> <span class="n">name</span>
<span class="p">}</span>
</pre></div>
</div>
<p>Here we reuse localizable, hopefully already translated literals (contained in
the <tt class="docutils literal"><span class="pre">verbose_name</span></tt> and <tt class="docutils literal"><span class="pre">verbose_name_plural</span></tt> model <tt class="docutils literal"><span class="pre">Meta</span></tt> options) for
other parts of the sentence so all of it is consistently based on the
cardinality of the elements at play.</p>
<div class="admonition note" id="pluralization-var-notes">
<p class="first admonition-title">Note</p>
<p>When using this technique, make sure you use a single name for every
extrapolated variable included in the literal. In the example above note how
we used the <tt class="docutils literal"><span class="pre">name</span></tt> Python variable in both translation strings. This
example would fail:</p>
<div class="highlight-python"><pre>from django.utils.translation import ungettext
from myapp.models import Report

count = Report.objects.count()
d = {
    'count': count,
    'name': Report._meta.verbose_name
    'plural_name': Report._meta.verbose_name_plural
}
text = ungettext(
        'There is %(count)d %(name)s available.',
        'There are %(count)d %(plural_name)s available.',
        count
) % d</pre>
</div>
<p class="last">You would get a <tt class="docutils literal"><span class="pre">a</span> <span class="pre">format</span> <span class="pre">specification</span> <span class="pre">for</span> <span class="pre">argument</span> <span class="pre">'name',</span> <span class="pre">as</span> <span class="pre">in</span>
<span class="pre">'msgstr[0]',</span> <span class="pre">doesn't</span> <span class="pre">exist</span> <span class="pre">in</span> <span class="pre">'msgid'</span></tt> error when running
<tt class="docutils literal"><span class="pre">django-admin.py</span> <span class="pre">compilemessages</span></tt> or a <tt class="docutils literal"><span class="pre">KeyError</span></tt> Python exception at
runtime.</p>
</div>
</div>
<div class="section" id="s-lazy-translation">
<span id="s-lazy-translations"></span><span id="lazy-translation"></span><span id="lazy-translations"></span><h3>Lazy translation<a class="headerlink" href="#lazy-translation" title="Permalink to this headline">¶</a></h3>
<p>Use the function <tt class="docutils literal"><span class="pre">django.utils.translation.ugettext_lazy()</span></tt> to translate
strings lazily -- when the value is accessed rather than when the
<tt class="docutils literal"><span class="pre">ugettext_lazy()</span></tt> function is called.</p>
<p>For example, to translate a model's <tt class="docutils literal"><span class="pre">help_text</span></tt>, do the following:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">django.utils.translation</span> <span class="kn">import</span> <span class="n">ugettext_lazy</span>

<span class="k">class</span> <span class="nc">MyThing</span><span class="p">(</span><span class="n">models</span><span class="o">.</span><span class="n">Model</span><span class="p">):</span>
    <span class="n">name</span> <span class="o">=</span> <span class="n">models</span><span class="o">.</span><span class="n">CharField</span><span class="p">(</span><span class="n">help_text</span><span class="o">=</span><span class="n">ugettext_lazy</span><span class="p">(</span><span class="s">&#39;This is the help text&#39;</span><span class="p">))</span>
</pre></div>
</div>
<p>In this example, <tt class="docutils literal"><span class="pre">ugettext_lazy()</span></tt> stores a lazy reference to the string --
not the actual translation. The translation itself will be done when the string
is used in a string context, such as template rendering on the Django admin
site.</p>
<p>The result of a <tt class="docutils literal"><span class="pre">ugettext_lazy()</span></tt> call can be used wherever you would use a
unicode string (an object with type <tt class="docutils literal"><span class="pre">unicode</span></tt>) in Python. If you try to use
it where a bytestring (a <tt class="docutils literal"><span class="pre">str</span></tt> object) is expected, things will not work as
expected, since a <tt class="docutils literal"><span class="pre">ugettext_lazy()</span></tt> object doesn't know how to convert
itself to a bytestring.  You can't use a unicode string inside a bytestring,
either, so this is consistent with normal Python behavior. For example:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="c"># This is fine: putting a unicode proxy into a unicode string.</span>
<span class="s">u&quot;Hello </span><span class="si">%s</span><span class="s">&quot;</span> <span class="o">%</span> <span class="n">ugettext_lazy</span><span class="p">(</span><span class="s">&quot;people&quot;</span><span class="p">)</span>

<span class="c"># This will not work, since you cannot insert a unicode object</span>
<span class="c"># into a bytestring (nor can you insert our unicode proxy there)</span>
<span class="s">&quot;Hello </span><span class="si">%s</span><span class="s">&quot;</span> <span class="o">%</span> <span class="n">ugettext_lazy</span><span class="p">(</span><span class="s">&quot;people&quot;</span><span class="p">)</span>
</pre></div>
</div>
<p>If you ever see output that looks like <tt class="docutils literal"><span class="pre">&quot;hello</span>
<span class="pre">&lt;django.utils.functional...&gt;&quot;</span></tt>, you have tried to insert the result of
<tt class="docutils literal"><span class="pre">ugettext_lazy()</span></tt> into a bytestring. That's a bug in your code.</p>
<p>If you don't like the verbose name <tt class="docutils literal"><span class="pre">ugettext_lazy</span></tt>, you can just alias it as
<tt class="docutils literal"><span class="pre">_</span></tt> (underscore), like so:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">django.utils.translation</span> <span class="kn">import</span> <span class="n">ugettext_lazy</span> <span class="k">as</span> <span class="n">_</span>

<span class="k">class</span> <span class="nc">MyThing</span><span class="p">(</span><span class="n">models</span><span class="o">.</span><span class="n">Model</span><span class="p">):</span>
    <span class="n">name</span> <span class="o">=</span> <span class="n">models</span><span class="o">.</span><span class="n">CharField</span><span class="p">(</span><span class="n">help_text</span><span class="o">=</span><span class="n">_</span><span class="p">(</span><span class="s">&#39;This is the help text&#39;</span><span class="p">))</span>
</pre></div>
</div>
<p>Always use lazy translations in <a class="reference internal" href="../db/models.html"><em>Django models</em></a>.
Field names and table names should be marked for translation (otherwise, they
won't be translated in the admin interface). This means writing explicit
<tt class="docutils literal"><span class="pre">verbose_name</span></tt> and <tt class="docutils literal"><span class="pre">verbose_name_plural</span></tt> options in the <tt class="docutils literal"><span class="pre">Meta</span></tt> class,
though, rather than relying on Django's default determination of
<tt class="docutils literal"><span class="pre">verbose_name</span></tt> and <tt class="docutils literal"><span class="pre">verbose_name_plural</span></tt> by looking at the model's class
name:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">django.utils.translation</span> <span class="kn">import</span> <span class="n">ugettext_lazy</span> <span class="k">as</span> <span class="n">_</span>

<span class="k">class</span> <span class="nc">MyThing</span><span class="p">(</span><span class="n">models</span><span class="o">.</span><span class="n">Model</span><span class="p">):</span>
    <span class="n">name</span> <span class="o">=</span> <span class="n">models</span><span class="o">.</span><span class="n">CharField</span><span class="p">(</span><span class="n">_</span><span class="p">(</span><span class="s">&#39;name&#39;</span><span class="p">),</span> <span class="n">help_text</span><span class="o">=</span><span class="n">_</span><span class="p">(</span><span class="s">&#39;This is the help text&#39;</span><span class="p">))</span>
    <span class="k">class</span> <span class="nc">Meta</span><span class="p">:</span>
        <span class="n">verbose_name</span> <span class="o">=</span> <span class="n">_</span><span class="p">(</span><span class="s">&#39;my thing&#39;</span><span class="p">)</span>
        <span class="n">verbose_name_plural</span> <span class="o">=</span> <span class="n">_</span><span class="p">(</span><span class="s">&#39;mythings&#39;</span><span class="p">)</span>
</pre></div>
</div>
</div>
<div class="section" id="s-working-with-lazy-translation-objects">
<span id="working-with-lazy-translation-objects"></span><h3>Working with lazy translation objects<a class="headerlink" href="#working-with-lazy-translation-objects" title="Permalink to this headline">¶</a></h3>
<p>Using <tt class="docutils literal"><span class="pre">ugettext_lazy()</span></tt> and <tt class="docutils literal"><span class="pre">ungettext_lazy()</span></tt> to mark strings in models
and utility functions is a common operation. When you're working with these
objects elsewhere in your code, you should ensure that you don't accidentally
convert them to strings, because they should be converted as late as possible
(so that the correct locale is in effect). This necessitates the use of a
couple of helper functions.</p>
<div class="section" id="s-joining-strings-string-concat">
<span id="joining-strings-string-concat"></span><h4>Joining strings: string_concat()<a class="headerlink" href="#joining-strings-string-concat" title="Permalink to this headline">¶</a></h4>
<p>Standard Python string joins (<tt class="docutils literal"><span class="pre">''.join([...])</span></tt>) will not work on lists
containing lazy translation objects. Instead, you can use
<tt class="docutils literal"><span class="pre">django.utils.translation.string_concat()</span></tt>, which creates a lazy object that
concatenates its contents <em>and</em> converts them to strings only when the result
is included in a string. For example:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">django.utils.translation</span> <span class="kn">import</span> <span class="n">string_concat</span>
<span class="o">...</span>
<span class="n">name</span> <span class="o">=</span> <span class="n">ugettext_lazy</span><span class="p">(</span><span class="s">u&#39;John Lennon&#39;</span><span class="p">)</span>
<span class="n">instrument</span> <span class="o">=</span> <span class="n">ugettext_lazy</span><span class="p">(</span><span class="s">u&#39;guitar&#39;</span><span class="p">)</span>
<span class="n">result</span> <span class="o">=</span> <span class="n">string_concat</span><span class="p">(</span><span class="n">name</span><span class="p">,</span> <span class="s">&#39;: &#39;</span><span class="p">,</span> <span class="n">instrument</span><span class="p">)</span>
</pre></div>
</div>
<p>In this case, the lazy translations in <tt class="docutils literal"><span class="pre">result</span></tt> will only be converted to
strings when <tt class="docutils literal"><span class="pre">result</span></tt> itself is used in a string (usually at template
rendering time).</p>
</div>
<div class="section" id="s-the-allow-lazy-decorator">
<span id="the-allow-lazy-decorator"></span><h4>The allow_lazy() decorator<a class="headerlink" href="#the-allow-lazy-decorator" title="Permalink to this headline">¶</a></h4>
<p>Django offers many utility functions (particularly in <tt class="docutils literal"><span class="pre">django.utils</span></tt>) that
take a string as their first argument and do something to that string. These
functions are used by template filters as well as directly in other code.</p>
<p>If you write your own similar functions and deal with translations, you'll
face the problem of what to do when the first argument is a lazy translation
object. You don't want to convert it to a string immediately, because you might
be using this function outside of a view (and hence the current thread's locale
setting will not be correct).</p>
<p>For cases like this, use the <tt class="docutils literal"><span class="pre">django.utils.functional.allow_lazy()</span></tt>
decorator. It modifies the function so that <em>if</em> it's called with a lazy
translation as the first argument, the function evaluation is delayed until it
needs to be converted to a string.</p>
<p>For example:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">django.utils.functional</span> <span class="kn">import</span> <span class="n">allow_lazy</span>

<span class="k">def</span> <span class="nf">fancy_utility_function</span><span class="p">(</span><span class="n">s</span><span class="p">,</span> <span class="o">...</span><span class="p">):</span>
    <span class="c"># Do some conversion on string &#39;s&#39;</span>
    <span class="o">...</span>
<span class="n">fancy_utility_function</span> <span class="o">=</span> <span class="n">allow_lazy</span><span class="p">(</span><span class="n">fancy_utility_function</span><span class="p">,</span> <span class="nb">unicode</span><span class="p">)</span>
</pre></div>
</div>
<p>The <tt class="docutils literal"><span class="pre">allow_lazy()</span></tt> decorator takes, in addition to the function to decorate,
a number of extra arguments (<tt class="docutils literal"><span class="pre">*args</span></tt>) specifying the type(s) that the
original function can return. Usually, it's enough to include <tt class="docutils literal"><span class="pre">unicode</span></tt> here
and ensure that your function returns only Unicode strings.</p>
<p>Using this decorator means you can write your function and assume that the
input is a proper string, then add support for lazy translation objects at the
end.</p>
</div>
</div>
</div>
<div class="section" id="s-specifying-translation-strings-in-template-code">
<span id="s-id1"></span><span id="specifying-translation-strings-in-template-code"></span><span id="id1"></span><h2>Specifying translation strings: In template code<a class="headerlink" href="#specifying-translation-strings-in-template-code" title="Permalink to this headline">¶</a></h2>
<p>Translations in <a class="reference internal" href="../templates.html"><em>Django templates</em></a> uses two template
tags and a slightly different syntax than in Python code. To give your template
access to these tags, put <tt class="docutils literal"><span class="pre">{%</span> <span class="pre">load</span> <span class="pre">i18n</span> <span class="pre">%}</span></tt> toward the top of your template.</p>
<div class="section" id="s-trans-template-tag">
<span id="trans-template-tag"></span><h3><tt class="docutils literal"><span class="pre">trans</span></tt> template tag<a class="headerlink" href="#trans-template-tag" title="Permalink to this headline">¶</a></h3>
<p>The <tt class="docutils literal"><span class="pre">{%</span> <span class="pre">trans</span> <span class="pre">%}</span></tt> template tag translates either a constant string
(enclosed in single or double quotes) or variable content:</p>
<div class="highlight-html+django"><div class="highlight"><pre><span class="nt">&lt;title&gt;</span><span class="cp">{%</span> <span class="k">trans</span> <span class="s2">&quot;This is the title.&quot;</span> <span class="cp">%}</span><span class="nt">&lt;/title&gt;</span>
<span class="nt">&lt;title&gt;</span><span class="cp">{%</span> <span class="k">trans</span> <span class="nv">myvar</span> <span class="cp">%}</span><span class="nt">&lt;/title&gt;</span>
</pre></div>
</div>
<p>If the <tt class="docutils literal"><span class="pre">noop</span></tt> option is present, variable lookup still takes place but the
translation is skipped. This is useful when &quot;stubbing out&quot; content that will
require translation in the future:</p>
<div class="highlight-html+django"><div class="highlight"><pre><span class="nt">&lt;title&gt;</span><span class="cp">{%</span> <span class="k">trans</span> <span class="s2">&quot;myvar&quot;</span> <span class="nv">noop</span> <span class="cp">%}</span><span class="nt">&lt;/title&gt;</span>
</pre></div>
</div>
<p>Internally, inline translations use an <tt class="docutils literal"><span class="pre">ugettext</span></tt> call.</p>
<p>In case a template var (<tt class="docutils literal"><span class="pre">myvar</span></tt> above) is passed to the tag, the tag will
first resolve such variable to a string at run-time and then look up that
string in the message catalogs.</p>
<p>It's not possible to mix a template variable inside a string within <tt class="docutils literal"><span class="pre">{%</span> <span class="pre">trans</span>
<span class="pre">%}</span></tt>. If your translations require strings with variables (placeholders), use
<tt class="docutils literal"><span class="pre">{%</span> <span class="pre">blocktrans</span> <span class="pre">%}</span></tt> instead.</p>
</div>
<div class="section" id="s-blocktrans-template-tag">
<span id="blocktrans-template-tag"></span><h3><tt class="docutils literal"><span class="pre">blocktrans</span></tt> template tag<a class="headerlink" href="#blocktrans-template-tag" title="Permalink to this headline">¶</a></h3>
<p>Contrarily to the <tt class="docutils literal"><span class="pre">trans</span></tt> tag, the <tt class="docutils literal"><span class="pre">blocktrans</span></tt> tag allows you to mark
complex sentences consisting of literals and variable content for translation
by making use of placeholders:</p>
<div class="highlight-html+django"><div class="highlight"><pre><span class="cp">{%</span> <span class="k">blocktrans</span> <span class="cp">%}</span>This string will have <span class="cp">{{</span> <span class="nv">value</span> <span class="cp">}}</span> inside.<span class="cp">{%</span> <span class="k">endblocktrans</span> <span class="cp">%}</span>
</pre></div>
</div>
<p>To translate a template expression -- say, accessing object attributes or
using template filters -- you need to bind the expression to a local variable
for use within the translation block. Examples:</p>
<div class="highlight-html+django"><div class="highlight"><pre><span class="cp">{%</span> <span class="k">blocktrans</span> <span class="k">with</span> <span class="nv">article.price</span> <span class="k">as</span> <span class="nv">amount</span> <span class="cp">%}</span>
That will cost $ <span class="cp">{{</span> <span class="nv">amount</span> <span class="cp">}}</span>.
<span class="cp">{%</span> <span class="k">endblocktrans</span> <span class="cp">%}</span>

<span class="cp">{%</span> <span class="k">blocktrans</span> <span class="k">with</span> <span class="nv">value</span><span class="o">|</span><span class="nf">filter</span> <span class="k">as</span> <span class="nv">myvar</span> <span class="cp">%}</span>
This will have <span class="cp">{{</span> <span class="nv">myvar</span> <span class="cp">}}</span> inside.
<span class="cp">{%</span> <span class="k">endblocktrans</span> <span class="cp">%}</span>
</pre></div>
</div>
<p>If you need to bind more than one expression inside a <tt class="docutils literal"><span class="pre">blocktrans</span></tt> tag,
separate the pieces with <tt class="docutils literal"><span class="pre">and</span></tt>:</p>
<div class="highlight-html+django"><div class="highlight"><pre><span class="cp">{%</span> <span class="k">blocktrans</span> <span class="k">with</span> <span class="nv">book</span><span class="o">|</span><span class="nf">title</span> <span class="k">as</span> <span class="nv">book_t</span> <span class="k">and</span> <span class="nv">author</span><span class="o">|</span><span class="nf">title</span> <span class="k">as</span> <span class="nv">author_t</span> <span class="cp">%}</span>
This is <span class="cp">{{</span> <span class="nv">book_t</span> <span class="cp">}}</span> by <span class="cp">{{</span> <span class="nv">author_t</span> <span class="cp">}}</span>
<span class="cp">{%</span> <span class="k">endblocktrans</span> <span class="cp">%}</span>
</pre></div>
</div>
<p>This tag is also in charge of handling another functionality: Pluralization.
To make use of it you should:</p>
<ul class="simple">
<li>Designate and bind a counter value by using <tt class="docutils literal"><span class="pre">count</span></tt>, such value will
be the one used to select the right plural form.</li>
<li>Specify both the singular and plural forms separating them with the
<tt class="docutils literal"><span class="pre">{%</span> <span class="pre">plural</span> <span class="pre">%}</span></tt> tag, which appears within <tt class="docutils literal"><span class="pre">{%</span> <span class="pre">blocktrans</span> <span class="pre">%}</span></tt> and
<tt class="docutils literal"><span class="pre">{%</span> <span class="pre">endblocktrans</span> <span class="pre">%}</span></tt>.</li>
</ul>
<p>An example:</p>
<div class="highlight-html+django"><div class="highlight"><pre><span class="cp">{%</span> <span class="k">blocktrans</span> <span class="nv">count</span> <span class="nv">list</span><span class="o">|</span><span class="nf">length</span> <span class="k">as</span> <span class="nv">counter</span> <span class="cp">%}</span>
There is only one <span class="cp">{{</span> <span class="nv">name</span> <span class="cp">}}</span> object.
<span class="cp">{%</span> <span class="k">plural</span> <span class="cp">%}</span>
There are <span class="cp">{{</span> <span class="nv">counter</span> <span class="cp">}}</span> <span class="cp">{{</span> <span class="nv">name</span> <span class="cp">}}</span> objects.
<span class="cp">{%</span> <span class="k">endblocktrans</span> <span class="cp">%}</span>
</pre></div>
</div>
<p>A more complex example:</p>
<div class="highlight-html+django"><div class="highlight"><pre><span class="cp">{%</span> <span class="k">blocktrans</span> <span class="k">with</span> <span class="nv">article.price</span> <span class="k">as</span> <span class="nv">amount</span> <span class="nv">count</span> <span class="nv">i.length</span> <span class="k">as</span> <span class="nv">years</span> <span class="cp">%}</span>
That will cost $ <span class="cp">{{</span> <span class="nv">amount</span> <span class="cp">}}</span> per year.
<span class="cp">{%</span> <span class="k">plural</span> <span class="cp">%}</span>
That will cost $ <span class="cp">{{</span> <span class="nv">amount</span> <span class="cp">}}</span> per <span class="cp">{{</span> <span class="nv">years</span> <span class="cp">}}</span> years.
<span class="cp">{%</span> <span class="k">endblocktrans</span> <span class="cp">%}</span>
</pre></div>
</div>
<p>When you both use the pluralization feature and bind values to local variables
in addition to the counter value, have in mind that the <tt class="docutils literal"><span class="pre">blocktrans</span></tt>
construct is internally converted to an <tt class="docutils literal"><span class="pre">ungettext</span></tt> call. This means the
same <a class="reference internal" href="#pluralization-var-notes"><em>notes regarding ungettext variables</em></a>
apply.</p>
</div>
<div class="section" id="s-other-tags">
<span id="s-template-translation-vars"></span><span id="other-tags"></span><span id="template-translation-vars"></span><h3>Other tags<a class="headerlink" href="#other-tags" title="Permalink to this headline">¶</a></h3>
<p>Each <tt class="docutils literal"><span class="pre">RequestContext</span></tt> has access to three translation-specific variables:</p>
<ul class="simple">
<li><tt class="docutils literal"><span class="pre">LANGUAGES</span></tt> is a list of tuples in which the first element is the
<a class="reference internal" href="index.html#term-language-code"><em class="xref std std-term">language code</em></a> and the second is the language name (translated into
the currently active locale).</li>
<li><tt class="docutils literal"><span class="pre">LANGUAGE_CODE</span></tt> is the current user's preferred language, as a string.
Example: <tt class="docutils literal"><span class="pre">en-us</span></tt>. (See <a class="reference internal" href="deployment.html#how-django-discovers-language-preference"><em>How Django discovers language preference</em></a>.)</li>
<li><tt class="docutils literal"><span class="pre">LANGUAGE_BIDI</span></tt> is the current locale's direction. If True, it's a
right-to-left language, e.g.: Hebrew, Arabic. If False it's a
left-to-right language, e.g.: English, French, German etc.</li>
</ul>
<p>If you don't use the <tt class="docutils literal"><span class="pre">RequestContext</span></tt> extension, you can get those values with
three tags:</p>
<div class="highlight-html+django"><div class="highlight"><pre><span class="cp">{%</span> <span class="k">get_current_language</span> <span class="k">as</span> <span class="nv">LANGUAGE_CODE</span> <span class="cp">%}</span>
<span class="cp">{%</span> <span class="k">get_available_languages</span> <span class="k">as</span> <span class="nv">LANGUAGES</span> <span class="cp">%}</span>
<span class="cp">{%</span> <span class="k">get_current_language_bidi</span> <span class="k">as</span> <span class="nv">LANGUAGE_BIDI</span> <span class="cp">%}</span>
</pre></div>
</div>
<p>These tags also require a <tt class="docutils literal"><span class="pre">{%</span> <span class="pre">load</span> <span class="pre">i18n</span> <span class="pre">%}</span></tt>.</p>
<p>Translation hooks are also available within any template block tag that accepts
constant strings. In those cases, just use <tt class="docutils literal"><span class="pre">_()</span></tt> syntax to specify a
translation string:</p>
<div class="highlight-html+django"><div class="highlight"><pre><span class="cp">{%</span> <span class="k">some_special_tag</span> <span class="kp">_</span><span class="o">(</span><span class="s2">&quot;Page not found&quot;</span><span class="o">)</span> <span class="nv">value</span><span class="o">|</span><span class="nf">yesno</span><span class="o">:</span><span class="kp">_</span><span class="o">(</span><span class="s2">&quot;yes,no&quot;</span><span class="o">)</span> <span class="cp">%}</span>
</pre></div>
</div>
<p>In this case, both the tag and the filter will see the already-translated
string, so they don't need to be aware of translations.</p>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">In this example, the translation infrastructure will be passed the string
<tt class="docutils literal"><span class="pre">&quot;yes,no&quot;</span></tt>, not the individual strings <tt class="docutils literal"><span class="pre">&quot;yes&quot;</span></tt> and <tt class="docutils literal"><span class="pre">&quot;no&quot;</span></tt>. The
translated string will need to contain the comma so that the filter
parsing code knows how to split up the arguments. For example, a German
translator might translate the string <tt class="docutils literal"><span class="pre">&quot;yes,no&quot;</span></tt> as <tt class="docutils literal"><span class="pre">&quot;ja,nein&quot;</span></tt>
(keeping the comma intact).</p>
</div>
</div>
</div>
<div class="section" id="s-specifying-translation-strings-in-javascript-code">
<span id="specifying-translation-strings-in-javascript-code"></span><h2>Specifying translation strings: In JavaScript code<a class="headerlink" href="#specifying-translation-strings-in-javascript-code" title="Permalink to this headline">¶</a></h2>
<p>Adding translations to JavaScript poses some problems:</p>
<ul class="simple">
<li>JavaScript code doesn't have access to a <tt class="docutils literal"><span class="pre">gettext</span></tt> implementation.</li>
<li>JavaScript code doesn't have access to .po or .mo files; they need to be
delivered by the server.</li>
<li>The translation catalogs for JavaScript should be kept as small as
possible.</li>
</ul>
<p>Django provides an integrated solution for these problems: It passes the
translations into JavaScript, so you can call <tt class="docutils literal"><span class="pre">gettext</span></tt>, etc., from within
JavaScript.</p>
<div class="section" id="s-module-django.views.i18n">
<span id="s-the-javascript-catalog-view"></span><span id="module-django.views.i18n"></span><span id="the-javascript-catalog-view"></span><h3>The <tt class="docutils literal"><span class="pre">javascript_catalog</span></tt> view<a class="headerlink" href="#module-django.views.i18n" title="Permalink to this headline">¶</a></h3>
<dl class="function">
<dt id="django.views.i18n.javascript_catalog">
<tt class="descname">javascript_catalog</tt>(<em>request</em>, <em>domain='djangojs'</em>, <em>packages=None</em>)<a class="headerlink" href="#django.views.i18n.javascript_catalog" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

<p>The main solution to these problems is the <a class="reference internal" href="#django.views.i18n.javascript_catalog" title="django.views.i18n.javascript_catalog"><tt class="xref py py-meth docutils literal"><span class="pre">django.views.i18n.javascript_catalog()</span></tt></a>
view, which sends out a JavaScript code library with functions that mimic the
<tt class="docutils literal"><span class="pre">gettext</span></tt> interface, plus an array of translation strings. Those translation
strings are taken from the application, project or Django core, according to what
you specify in either the info_dict or the URL.</p>
<p>You hook it up like this:</p>
<div class="highlight-html+django"><div class="highlight"><pre>js_info_dict = {
    &#39;packages&#39;: (&#39;your.app.package&#39;,),
}

urlpatterns = patterns(&#39;&#39;,
    (r&#39;^jsi18n/$&#39;, &#39;django.views.i18n.javascript_catalog&#39;, js_info_dict),
)
</pre></div>
</div>
<p>Each string in <tt class="docutils literal"><span class="pre">packages</span></tt> should be in Python dotted-package syntax (the
same format as the strings in <tt class="docutils literal"><span class="pre">INSTALLED_APPS</span></tt>) and should refer to a package
that contains a <tt class="docutils literal"><span class="pre">locale</span></tt> directory. If you specify multiple packages, all
those catalogs are merged into one catalog. This is useful if you have
JavaScript that uses strings from different applications.</p>
<p>By default, the view uses the <tt class="docutils literal"><span class="pre">djangojs</span></tt> gettext domain. This can be
changed by altering the <tt class="docutils literal"><span class="pre">domain</span></tt> argument.</p>
<p>You can make the view dynamic by putting the packages into the URL pattern:</p>
<div class="highlight-html+django"><div class="highlight"><pre>urlpatterns = patterns(&#39;&#39;,
    (r&#39;^jsi18n/(?P<span class="nt">&lt;packages&gt;</span>\S+?)/$&#39;, &#39;django.views.i18n.javascript_catalog&#39;),
)
</pre></div>
</div>
<p>With this, you specify the packages as a list of package names delimited by '+'
signs in the URL. This is especially useful if your pages use code from
different apps and this changes often and you don't want to pull in one big
catalog file. As a security measure, these values can only be either
<tt class="docutils literal"><span class="pre">django.conf</span></tt> or any package from the <tt class="docutils literal"><span class="pre">INSTALLED_APPS</span></tt> setting.</p>
</div>
<div class="section" id="s-using-the-javascript-translation-catalog">
<span id="using-the-javascript-translation-catalog"></span><h3>Using the JavaScript translation catalog<a class="headerlink" href="#using-the-javascript-translation-catalog" title="Permalink to this headline">¶</a></h3>
<p>To use the catalog, just pull in the dynamically generated script like this:</p>
<div class="highlight-html+django"><div class="highlight"><pre><span class="nt">&lt;script </span><span class="na">type=</span><span class="s">&quot;text/javascript&quot;</span> <span class="na">src=</span><span class="s">&quot;</span><span class="cp">{%</span> <span class="k">url</span> <span class="nv">django.views.i18n.javascript_catalog</span> <span class="cp">%}</span><span class="s">&quot;</span><span class="nt">&gt;&lt;/script&gt;</span>
</pre></div>
</div>
<p>This uses reverse URL lookup to find the URL of the JavaScript catalog view.
When the catalog is loaded, your JavaScript code can use the standard
<tt class="docutils literal"><span class="pre">gettext</span></tt> interface to access it:</p>
<div class="highlight-html+django"><div class="highlight"><pre>document.write(gettext(&#39;this is to be translated&#39;));
</pre></div>
</div>
<p>There is also an <tt class="docutils literal"><span class="pre">ngettext</span></tt> interface:</p>
<div class="highlight-html+django"><div class="highlight"><pre>var object_cnt = 1 // or 0, or 2, or 3, ...
s = ngettext(&#39;literal for the singular case&#39;,
        &#39;literal for the plural case&#39;, object_cnt);
</pre></div>
</div>
<p>and even a string interpolation function:</p>
<div class="highlight-html+django"><div class="highlight"><pre>function interpolate(fmt, obj, named);
</pre></div>
</div>
<p>The interpolation syntax is borrowed from Python, so the <tt class="docutils literal"><span class="pre">interpolate</span></tt>
function supports both positional and named interpolation:</p>
<ul>
<li><p class="first">Positional interpolation: <tt class="docutils literal"><span class="pre">obj</span></tt> contains a JavaScript Array object
whose elements values are then sequentially interpolated in their
corresponding <tt class="docutils literal"><span class="pre">fmt</span></tt> placeholders in the same order they appear.
For example:</p>
<div class="highlight-html+django"><div class="highlight"><pre>fmts = ngettext(&#39;There is %s object. Remaining: %s&#39;,
        &#39;There are %s objects. Remaining: %s&#39;, 11);
s = interpolate(fmts, [11, 20]);
// s is &#39;There are 11 objects. Remaining: 20&#39;
</pre></div>
</div>
</li>
<li><p class="first">Named interpolation: This mode is selected by passing the optional
boolean <tt class="docutils literal"><span class="pre">named</span></tt> parameter as true. <tt class="docutils literal"><span class="pre">obj</span></tt> contains a JavaScript
object or associative array. For example:</p>
<div class="highlight-html+django"><div class="highlight"><pre>d = {
    count: 10,
    total: 50
};

fmts = ngettext(&#39;Total: %(total)s, there is %(count)s object&#39;,
&#39;there are %(count)s of a total of %(total)s objects&#39;, d.count);
s = interpolate(fmts, d, true);
</pre></div>
</div>
</li>
</ul>
<p>You shouldn't go over the top with string interpolation, though: this is still
JavaScript, so the code has to make repeated regular-expression substitutions.
This isn't as fast as string interpolation in Python, so keep it to those
cases where you really need it (for example, in conjunction with <tt class="docutils literal"><span class="pre">ngettext</span></tt>
to produce proper pluralizations).</p>
</div>
</div>
<div class="section" id="s-the-set-language-redirect-view">
<span id="the-set-language-redirect-view"></span><h2>The <tt class="docutils literal"><span class="pre">set_language</span></tt> redirect view<a class="headerlink" href="#the-set-language-redirect-view" title="Permalink to this headline">¶</a></h2>
<dl class="function">
<dt id="django.views.i18n.set_language">
<tt class="descname">set_language</tt>(<em>request</em>)<a class="headerlink" href="#django.views.i18n.set_language" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>

<p>As a convenience, Django comes with a view, <a class="reference internal" href="#django.views.i18n.set_language" title="django.views.i18n.set_language"><tt class="xref py py-meth docutils literal"><span class="pre">django.views.i18n.set_language()</span></tt></a>,
that sets a user's language preference and redirects back to the previous page.</p>
<p>Activate this view by adding the following line to your URLconf:</p>
<div class="highlight-html+django"><div class="highlight"><pre>(r&#39;^i18n/&#39;, include(&#39;django.conf.urls.i18n&#39;)),
</pre></div>
</div>
<p>(Note that this example makes the view available at <tt class="docutils literal"><span class="pre">/i18n/setlang/</span></tt>.)</p>
<p>The view expects to be called via the <tt class="docutils literal"><span class="pre">POST</span></tt> method, with a <tt class="docutils literal"><span class="pre">language</span></tt>
parameter set in request. If session support is enabled, the view
saves the language choice in the user's session. Otherwise, it saves the
language choice in a cookie that is by default named <tt class="docutils literal"><span class="pre">django_language</span></tt>.
(The name can be changed through the <tt class="docutils literal"><span class="pre">LANGUAGE_COOKIE_NAME</span></tt> setting.)</p>
<p>After setting the language choice, Django redirects the user, following this
algorithm:</p>
<ul class="simple">
<li>Django looks for a <tt class="docutils literal"><span class="pre">next</span></tt> parameter in the <tt class="docutils literal"><span class="pre">POST</span></tt> data.</li>
<li>If that doesn't exist, or is empty, Django tries the URL in the
<tt class="docutils literal"><span class="pre">Referrer</span></tt> header.</li>
<li>If that's empty -- say, if a user's browser suppresses that header --
then the user will be redirected to <tt class="docutils literal"><span class="pre">/</span></tt> (the site root) as a fallback.</li>
</ul>
<p>Here's example HTML template code:</p>
<div class="highlight-html+django"><div class="highlight"><pre><span class="nt">&lt;form</span> <span class="na">action=</span><span class="s">&quot;/i18n/setlang/&quot;</span> <span class="na">method=</span><span class="s">&quot;post&quot;</span><span class="nt">&gt;</span>
<span class="cp">{%</span> <span class="k">csrf_token</span> <span class="cp">%}</span>
<span class="nt">&lt;input</span> <span class="na">name=</span><span class="s">&quot;next&quot;</span> <span class="na">type=</span><span class="s">&quot;hidden&quot;</span> <span class="na">value=</span><span class="s">&quot;/next/page/&quot;</span> <span class="nt">/&gt;</span>
<span class="nt">&lt;select</span> <span class="na">name=</span><span class="s">&quot;language&quot;</span><span class="nt">&gt;</span>
<span class="cp">{%</span> <span class="k">for</span> <span class="nv">lang</span> <span class="k">in</span> <span class="nv">LANGUAGES</span> <span class="cp">%}</span>
<span class="nt">&lt;option</span> <span class="na">value=</span><span class="s">&quot;</span><span class="cp">{{</span> <span class="nv">lang.0</span> <span class="cp">}}</span><span class="s">&quot;</span><span class="nt">&gt;</span><span class="cp">{{</span> <span class="nv">lang.1</span> <span class="cp">}}</span><span class="nt">&lt;/option&gt;</span>
<span class="cp">{%</span> <span class="k">endfor</span> <span class="cp">%}</span>
<span class="nt">&lt;/select&gt;</span>
<span class="nt">&lt;input</span> <span class="na">type=</span><span class="s">&quot;submit&quot;</span> <span class="na">value=</span><span class="s">&quot;Go&quot;</span> <span class="nt">/&gt;</span>
<span class="nt">&lt;/form&gt;</span>
</pre></div>
</div>
</div>
</div>


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  <h3><a href="../../contents.html">Table Of Contents</a></h3>
  <ul>
<li><a class="reference internal" href="#">Internationalization</a><ul>
<li><a class="reference internal" href="#overview">Overview</a></li>
<li><a class="reference internal" href="#specifying-translation-strings-in-python-code">Specifying translation strings: In Python code</a><ul>
<li><a class="reference internal" href="#standard-translation">Standard translation</a></li>
<li><a class="reference internal" href="#marking-strings-as-no-op">Marking strings as no-op</a></li>
<li><a class="reference internal" href="#pluralization">Pluralization</a></li>
<li><a class="reference internal" href="#lazy-translation">Lazy translation</a></li>
<li><a class="reference internal" href="#working-with-lazy-translation-objects">Working with lazy translation objects</a><ul>
<li><a class="reference internal" href="#joining-strings-string-concat">Joining strings: string_concat()</a></li>
<li><a class="reference internal" href="#the-allow-lazy-decorator">The allow_lazy() decorator</a></li>
</ul>
</li>
</ul>
</li>
<li><a class="reference internal" href="#specifying-translation-strings-in-template-code">Specifying translation strings: In template code</a><ul>
<li><a class="reference internal" href="#trans-template-tag"><tt class="docutils literal"><span class="pre">trans</span></tt> template tag</a></li>
<li><a class="reference internal" href="#blocktrans-template-tag"><tt class="docutils literal"><span class="pre">blocktrans</span></tt> template tag</a></li>
<li><a class="reference internal" href="#other-tags">Other tags</a></li>
</ul>
</li>
<li><a class="reference internal" href="#specifying-translation-strings-in-javascript-code">Specifying translation strings: In JavaScript code</a><ul>
<li><a class="reference internal" href="#module-django.views.i18n">The <tt class="docutils literal"><span class="pre">javascript_catalog</span></tt> view</a></li>
<li><a class="reference internal" href="#using-the-javascript-translation-catalog">Using the JavaScript translation catalog</a></li>
</ul>
</li>
<li><a class="reference internal" href="#the-set-language-redirect-view">The <tt class="docutils literal"><span class="pre">set_language</span></tt> redirect view</a></li>
</ul>
</li>
</ul>

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