Array Destructuring ([] = …)

Also Known As

TL;DR

Explanation

Array destructuring (PHP 7.1+) uses [] = syntax as shorthand for the older list() = form. Both positional and key-based forms are supported: [$first, $second] = $arr and ['name' => $name, 'age' => $age] = $row. Elements can be skipped: [, $second] = $pair. Particularly readable in foreach: foreach ($rows as ['id' => $id, 'email' => $email]). PHP 8.1 added support for destructuring in more contexts. The feature improves readability over multiple explicit index accesses and makes tuple-style returns from functions practical.

Common Misconception

Why It Matters

Common Mistakes

• Using list() or [] destructuring without checking that the array has the expected keys first — undefined index notices on missing keys.
• Destructuring numerically-indexed arrays by position when the array structure may change — use named keys instead.
• Not using the short [] syntax (PHP 7.1+) when list() is only being used for clarity — both work but [] is preferred.
• Ignoring values with a placeholder: [$first, , $third] is valid and clearer than skipping the index check.

Code Examples

// Fragile index-based access instead of destructuring:
$coords = getCoordinates();
$lat = $coords[0]; // What's index 0?
$lon = $coords[1];

// Better:
['lat' => $lat, 'lon' => $lon] = getCoordinates();

// Key-based in a loop
foreach ($users as ['id' => $id, 'email' => $email]) {
    sendNotification($id, $email);
}

References

• ↗ https://www.php.net/manual/en/language.types.array.php#language.types.array.destructuring

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