The null PHP cheatsheet : null coalescing and nullsafe operators

This is a small cheatsheet on PHP null coalescing and nullsafe operators, which allow to easily handle null objects and values in PHP.

Null coalescing operator

The null coalescing operator ?? was introduced in PHP 7 and allows to avoid heavy constructions with if (isset(...)). The null coalescing operator returns the first operand if it is not null, and otherwise the second operand.

$username = $_GET['username'] ?? 'nobody';

// is equivalent to:
$username = isset($_GET['username']) ? $_GET['username'] : 'nobody';

Nullsafe operator

The nullsafe Operator ?-> was introduced in PHP 8 and provides a concise way to access object properties or methods only if the object is not null. Hence this allows to easily avoid errors like Fatal error: Uncaught Error: Attempt to read property "location" on null.

$location = $user->profile?->location;

// is equivalent to:
if (is_null($user->profile)) {
  $location = null;
} else {
  $location = $user->profile->location;
}

This was a short post, but on two powerful features in PHP. The null coalescing operator (??) and the nullsafe operator (?->) allow developers to write more concise and error-free code, reducing the likelihood of null pointer exceptions and improving the overall maintainability of applications.

This blog post is licensed under CC BY-SA 4.0