{% for item in items %}
loop start
{% outer %}
{% item.value %}
{% item.nested.value %}
{% does_not_exist %}
loop end
{% end %}

{% for item in empty %}
{% else %}
else
{% end %}

{% for item in non_existent %}
{% else %}
else
{% end %}

{% for item in items %}
  0-based index: {% loop.index0 %}
  1-based index: {% loop.index1 %}
  true if this is the first iteration: {% loop.first %}
  true if this is the last iteration: {% loop.last %}
  the number of iterations in the loop: {% loop.size %}
  alternate items in an array, treating it as circular: {% loop.index0 | alternate(["one", "two", "three"]) %}
{% end %}