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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 - 8.2.31, 8.3.0 - 8.3.31, 8.4.1 - 8.4.22, 8.5.0 - 8.5.7
5

preferences:
62.37 ms | 979 KiB | 4 Q