How can I use break and continue in Django templates?

Question

I want to put break and continue in my code, but it doesn't work in Django template. How can I use continue and break using Django template for loop. Here is an example:

{% for i in i_range %}
{% for frequency in patient_meds.frequency %}
{% ifequal frequency i %}
<td class="nopad"><input type="checkbox" name="frequency-1" value="{{ i }}" checked/> {{ i }} AM</td>
{{ forloop.parentloop|continue }} ////// It doesn't work
{ continue }                      ////// It also doesn't work
{% endifequal %}
{% endfor%}
<td class="nopad"><input type="checkbox" name="frequency-1" value="{{ i }}"/> {{ i }} AM</td>
{% endfor %}

You need to be clearer. Is this a python problem or a django template problem? Normally templates shouldn't have such logic in them. Can you post a simple example with some code? — Spacedman, Feb 07 '11 at 11:59
You will have to show us the code that does not work and explain how it fails (for example by copying the exact error message into your question). — Sven Marnach, Feb 07 '11 at 11:59
% for i in i_range %} {% for frequency in patient_meds.frequency %} {% ifequal frequency i %} {{ i }} AM {{ forloop.parentloop|continue }} ////// I does'nt work { continue } ////// It also does'nt work {% endifequal %} {% endfor%} {{ i }} AM {% endfor %} — GoldenBird, Feb 07 '11 at 12:20

score 39 · Answer 1 · answered Nov 28 '11 at 15:36

39

Django doesn't support it naturally.

You can implement forloop|continue and forloop|break with custom filters.

http://djangosnippets.org/snippets/2093/

answered Nov 28 '11 at 15:36

Jasim Muhammed

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That's a LOT more code than I expected for implementing continue and break. – Mr. Lance E Sloan Apr 22 '21 at 19:38

Gintautas Miliauskas · Accepted Answer · 2011-02-11T23:38:33.097

37

For-loops in Django templates are different from plain Python for-loops, so continue and break will not work in them. See for yourself in the Django docs, there are no break or continue template tags. Given the overall position of Keep-It-Simple-Stupid in Django template syntax, you will probably have to find another way to accomplish what you need.

edited Feb 11 '11 at 23:38

answered Feb 07 '11 at 12:15

Gintautas Miliauskas

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thats true, but it's like limitation, not KISS. break is simple. example: stop iterate main loop if any nested loop produce enough items - very usefull and simple with break in template - neat template system like mako or cheetah have support for break/continue. – Sławomir Lenart Sep 16 '14 at 16:28
@ups in the example you've given you could simply use the template tag `slice` (example: `list|slice:":10"`) to limit the loop to a certain number of iterations, or even do it at the context level. – gdvalderrama Apr 01 '16 at 16:01

Sławomir Lenart · Answer 3 · 2023-04-18T15:25:23.947

16

For most of cases there is no need for custom templatetags, it's easy:

continue:

{% for each in iterable %}
  {% if conditions_for_continue %}
       <!-- continue -->
  {% else %}
       ... code ..
  {% endif %}
{% endfor %}

break use the same idea, but with the wider scope:

{% set stop_loop="" %}
{% for each in iterable %}
  {% if stop_loop %}{% else %}
       ... code ..
       under some condition {% set stop_loop="true" %}
       ... code ..
  {% endif %}
{% endfor %}

This is Jinja template, which you can easily use within Django b/c Jinja is built in.

You can use even both template backends in the same project (Jinja and Django template).

edited Apr 18 '23 at 15:25

answered Jul 06 '18 at 14:19

Sławomir Lenart

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This is Jinja templating. – HenryM Jun 12 '19 at 15:51
There is no `set` command in django template. – parmer_110 Mar 25 '23 at 20:06

score 2 · Answer 4 · edited Nov 04 '21 at 12:20

If you want a continue/break after certain conditions, I use the following Simple Tag as follows with "Vanilla" Django 3.2.5:

@register.simple_tag
def define(val=None):
  return val

Then you can use it as any variable in the template

{% define True as continue %}
      
{% for u in queryset  %}

  {% if continue %}

    {% if u.status.description == 'Passed' %}
      <td>Passed</td>
      
      {% define False as continue %}

    {% endif %}

  {% endif %}

{% endfor %}

Extremely useful for any type of variable you want to re-use on template without using with statements.

How can I use break and continue in Django templates?

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