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run code in 500+ PHP versions simultaneously
<?php class B { public readonly int $x; public function getX(): int { return $this->x; } } class C extends B { // Redeclare to make it writable. public readonly int $x; public function __construct() { $this->x = 5; } } $c = new C; print $c->getX();
Output for 8.1.0 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
5

preferences:
58.05 ms | 951 KiB | 4 Q