For

For

The for tag is the main iteration (loop) mechanism in Lava. While it's fairly simple to use it does have some powerful tools to allow you to do some creative things.

Basic Usages

The for tag is simple to implement over arrays of objects.

{% for campus in Campuses %}
    {{ campus.Name }}
{% endfor %}

Helper Variables

During every for loop the following helper variables are available to assist in building magic.

forloop.length total number of times the loop will iterate
forloop.index index of the current iteration
forloop.index0 zero based index of the current iteration
forloop.rindex number of iterations left
forloop.rindex0 zero based number of iterations left
forloop.first boolean set to true if this is the first iteration
forloop.last boolean set to true if this is the last iteration

Influencing Iterations

You can control the number, starting position and direction of your iterations. Don't believe us? Try these attributes...

limit:int limit to the number of interations
offset:int starts the interation at the nth item
reversed let the last be first and the first last (Matt 20:16)

Let's see that in action... all at once now...

{% for campus in Campuses limit:2 offset:1 reversed %}
    {{ campus.Name }}
{% endfor %}

An Alternate For Loop

There's a slightly different way to iterate through arrays. Consider the example below.

{% assign campusCount = Campuses | Size | Minus:1 %}

{% for i in (0..campusCount) %}
    {{ i | Plus:1 }}. {{ Campuses[i].Name }}
{% endfor %}

This is helpful as a replacement for a while loop. Consider this example where we'd like to list years starting from 2 years ago and ending with the current year.

{% assign currentYear = 'Now' | Date:'yyyy' %}
{% assign startYear = currentYear | Minus: 2 %}

{% for year in (startYear..currentYear) %}
    {{ year }}
{% endfor %}

Break and Continue Tags
v6.0

These two tags give you a little more control for those times when you just don't want to process through a whole list.

Break Usage

The break tag iterrupts processing inside a for loop and jumps out of the loop.

{% assign list = "1,2,3,4,5,6,7,8,9,10" | Split: "," %}
{% for i in list %}{{ i }}
{% if i > 3 %}{% break %}{% endif %}{% endfor %} -- output -- 1 2 3 4

Continue Usage

The continue tag iterrupts processing inside a for loop and skips to the next item in the loop.

{% assign list = "1,2,3,4,5,6,7,8,9,10" | Split: "," %}
{% for i in list %}{% if i == '3' %}{% continue %}{% endif %}{{ i }}
{% endfor %} -- output -- 1 2 4 5 6 7 8 9 10
More complex example skipping the 'Mobile' type number for Ted Decker
{% for phone in Person.PhoneNumbers %}
    {% if phone.NumberTypeValue.Value == 'Mobile' %}{% continue %}{% endif %}
    {{ phone.NumberTypeValue.Value }}: {{ phone.NumberFormatted }}
{% endfor %} -- output -- Home: (623) 555-3322 Work: (623) 555-2444
Note: Both break and continue tags, if used outside of a for loop, wiil abort the entire rendering, without any errors.