Setting element of array from Twig

Question

How can I set member of an already existing array from Twig?

I tried doing it next way:

{% set arr['element'] = 'value' %}

but I got the following error:

Unexpected token "punctuation" of value "[" ("end of statement block" expected) in ...

Answer 1

{% set links = {} %}

{# Use our array to wrap up our links. #}
{% for item in items %}
  {% set links = links|merge({ (loop.index0) : {'url': item.content['#url'].getUri(), 'text': item.content['#title']} }) %}
{% endfor %}

{%
set linkList = {
  'title': label,
  'links': links
}
%}

{% include '<to twig file>/link-list.twig'%}

Thanks for this thread -- I was also able to create an array with (loop.index0) and send to twig.

Answer 2

There is no nice way to do this in Twig. It is, however, possible by using the merge filter:

{% set arr = arr|merge({'element': 'value'}) %}

Answer 3

I've found this issue very annoying, and my solution is perhaps orthodox and not inline with the Twig philosophy, but I developed the following:

$function = new Twig_Function('set_element', function ($data, $key, $value) {
    // Assign value to $data[$key]
    if (!is_array($data)) {
        return $data;
    }
    $data[$key] = $value;
    return $data;
});
$twig->addFunction($function);

that can be used as follows:

{% set arr = set_element(arr, 'element', 'value') %}

Answer 4

I ran into this problem but was trying to create integer indexes instead of associative index like 'element'.

You need to protect your index key with () using the merge filter as well:

{% set arr = arr|merge({ (loop.index0): 'value'}) %} 

You can now add custom index key like ('element'~loop.index0)

Answer 5

I have tried @LivaX 's answer but it does not work , merging an array where keys are numeric wont work ( https://github.com/twigphp/Twig/issues/789 ).

That will work only when keys are strings

What I did is recreate another table ( temp) from the initial table (t) and make the keys a string , for example :

{% for key , value in t%}
{% set temp= temp|merge({(key~'_'):value}) %}
{% endfor %}

t keys : 0 , 1 , 2 ..

temp keys : 0_, 1_ , 2_ ....

Answer 6

If initialization only need:

{% set items = { 'apple': 'fruit', 'orange': 'fruit', 'peugeot': 'unknown' } %}