Using the null-coalescing Operator in Twig

Introduction

Recently, I wanted to simplify my Twig code by only showing a filled in “Other” value when an “Other” checkbox had been selected and the Other value filled in within a Symfony form that I developed. You can read up on how I developed that form in my Simplified Web Development with JSON and the Twig Ternary Operator.

My JSON code looks like the following:

{
   "License": true,
   "Transit": true,
   "No_Issues": false,
   "Friend": true,
   "Car": false,
   "Other": true,
   "Other_Value": "skateboard"
}

Where in this case “Other” is set to “true”, so Other was selected and the Other_Value was filled in and “skateboard” was entered in the form.

Rending in Twig

So now in my Twig template, I can use the null-coalescing operator which is in the form:

{{ foo ?? 'no' }}

The above code means, if foo is NOT defined, then show ‘no’. So in my case for the JSON I was using, I used the null-coalescing operator in my Twig template like so:

Other: {{ transport['Other_Value'] ?? '' }}

Which will simply display “skateboard” in this case. The code is very simple and is easy to re-use and support.

Hope this helps someone!