3v4l.org

run code in 500+ PHP versions simultaneously
<?php interface IPrinter { function print(PrintableValue $value): void; } class PrintableValue { public readonly mixed $value; public function __construct(mixed $value) { $this->value = $value; } public function __toString() { return json_encode($this->value); } } class ConsolePrinter implements IPrinter { function print(PrintableValue $value): void { echo $value; } } $printer = new ConsolePrinter; $value = new PrintableValue(['33']); $printer->print($value);
Output for 8.1.0 - 8.1.34, 8.2.0 - 8.2.32, 8.3.5 - 8.3.32, 8.4.1 - 8.4.23, 8.5.0 - 8.5.8
["33"]
Output for 8.0.1 - 8.0.30
Parse error: syntax error, unexpected identifier "mixed", expecting variable in /in/FcbPh on line 8
Process exited with code 255.
preferences:
59.39 ms | 1048 KiB | 4 Q