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python - Jinja2: Change the value of a variable inside a loop

I want to change the value of the variable declared outside the loop within a loop. But always changing, it keeps the initial value outside the loop.

{% set foo = False %}

{% for item in items %}
  {% set foo = True %}
  {% if foo %} Ok(1)! {% endif %}
{% endfor %}

{% if foo %} Ok(2)! {% endif %}

This renders:

Ok(1)!

So the only (bad) solution have found so far was this:

{% set foo = [] %}

{% for item in items %}
  {% if foo.append(True) %} {% endif %}
  {% if foo %} Ok(1)! {% endif %}
{% endfor %}

{% if foo %} Ok(2)! {% endif %}

This renders:

Ok(1)!
Ok(2)!

But, its is very ugly! Is there another more elegant solution?

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by (71.8m points)

Try also dictionary-based approach. It seems to be less ugly.

{% set vars = {'foo': False} %}

{% for item in items %}
  {% if vars.update({'foo': True}) %} {% endif %}
  {% if vars.foo %} Ok(1)! {% endif %}
{% endfor %}

{% if vars.foo %} Ok(2)! {% endif %}

This also renders:

Ok(1)!
Ok(2)!

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