How to call ucwords in twig?

Question

EDIT: Dec 3 2016

• Want to learn how to add custom extensions(filters) to twig? see this answer by lxg

• Do you just need to find the twig equivalent for ucwords? see this answer by Javier Eguiluz

I found several posts on calling php functions from twig, that show it should be supported, however it doesn't seem to work.

{{ ucwords( item|replace({'_':' '}) ) }}

results in :l

Slim Application Error

The application could not run because of the following error:

Details

Type: Twig_Error_Syntax Message: The function "ucwords" does not exist in "home.twig" at line 101

File: /usr/share/dev89/html/vhosts/local/libs/vendor/twig/twig/lib/Twig/ExpressionParser.php Line: 572

Answer 1

As @lxg said, it's not possible to call all PHP functions from Twig templates ... unless you want to do that and define your own filters/functions. Instead of a drawback, this is a good thing to "force" you to create good templates that don't contain too much logic.

Anyway, in this particular case, Twig already contains a filter called title which applies the "title case", which is equivalent to the ucwords() PHP function:

{{ item|replace({'_':' '})|title }}

Answer 2

Update: Twig 2.x comes with the capitalize filter which does exactly that.

---

It is not true that all PHP functions are available in Twig. Only a few Twig filters and functions go by the same names as their equivalents in PHP.

But you can easily create your own Twig extension for ucwords – filter as well as function:

<?php

namespace Acme\TestBundle\Twig;

class UcWordsExtension extends \Twig_Extension
{
    public function getFunctions()
    {
        return [
            new \Twig_SimpleFunction('ucwords', 'ucwords')
        ];
    }

    public function getFilters()
    {
        return [
            new \Twig_SimpleFilter('ucwords', 'ucwords')
        ];
    }
    
    public function getName()
    {
        return 'ext.ucwords';
    }

}

The first parameter of Twig_SimpleFunction/Twig_SimpleFilter is the name of the function/filter in Twig. The second parameter is a PHP callable. As the ucfirst function already exists, it is sufficient to pass its name as a string.

Test in Twig:

{{ "test foobar"|ucwords }} {# filter #} <br>
{{ ucwords("test foobar") }} {# function #} 

Returns:

Test Foobar
Test Foobar