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Tag for

Loop over each item in a sequence (also see iterator). For example, to display a list of users provided in a variable called users:

<h1>Members</h1>
<ul>
    {% for user in users %}
        <li>{{ user.username|e }}</li>
    {% endfor %}
</ul>

Note, however, that Lua tables (no array) are not ordered.

The else clause

If no iteration took place because the sequence was empty, you can render a replacement block by using else:

<ul>
    {% for user in users %}
        <li>{{ user.username|e }}</li>
    {% else %}
        <li><em>no user found</em></li>
    {% endfor %}
</ul>

Iterating over Keys

By default, a loop iterates over the values of the sequence. You can iterate on keys by using the keys filter:

<h1>Members</h1>
<ul>
    {% for key in users|keys %}
        <li>{{ key }}</li>
    {% endfor %}
</ul>

Iterating over Keys and Values

You can also access both keys and values:

<h1>Members</h1>
<ul>
    {% for key, user in users %}
        <li>{{ key }}: {{ user.username|e }}</li>
    {% endfor %}
</ul>

The loop variable

Inside of a for loop block you can access some special variables:

Variable	Description
loop.index	The current iteration of the loop. (1 indexed)
loop.index0	The current iteration of the loop. (0 indexed)
loop.revindex	The number of iterations from the end of the loop (1 indexed)
loop.revindex0	The number of iterations from the end of the loop (0 indexed)
loop.first	True if first iteration
loop.last	True if last iteration
loop.length	The number of items in the sequence
loop.parent	The parent context
loop.prev_item	The item from the previous iteration of the loop. Nil during the first iteration.
loop.next_item	The item from the following iteration of the loop. Nil during the last iteration.
loop.has_more	True if has more items.

Behavior

Value	action
string	not iterate
empty table	not iterate
number	not iterate
nil	not iterate
true/false	not iterate
userdata	not iterate
userdata with __pairs()	iterate with value:__pairs()
table	iterate with pairs()
table with __pairs()	iterate with value:__pairs() instead of pairs()