Implement "clone with"

[thekid]

class Person {
  public function __construct(public string $name) { }
}

$person= new Person('Test');
$clone= clone($person, ['name' => 'Clone of Test']);

Implementation status

• Clone with syntax
• Clone first-class callable syntax clone(...)
• Clone with unpacking (e.g. clone(...[$object, $properties]))
• Error compatibility for visibility mismatches: Could be done via reflection but with a significant performance cost
• Clone as callable (e.g. array_map('clone', $array) - not feasible

See also:

• https://wiki.php.net/rfc/clone_with_v2
• RFC: Clone with v2 php/php-src#18747
• Implement "clone with" ast#56

[thekid]

Vote started on June 4th, 2025: https://externals.io/message/127588

[thekid]

Once the PR in php-src is merged, we can drop these and natively emit clone expressions as function calls with their arguments.