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run code in 500+ PHP versions simultaneously
<?php class Foo { private function &getState(): array { static $state = ['counter' => 0]; return $state; } public function count(): int { return $this->getState()['counter']++; } } $x = new Foo(); $y = new Foo(); var_dump($x->count(), $y->count());;
Output for 8.1.34, 8.2.0 - 8.2.32, 8.3.0 - 8.3.33, 8.4.1 - 8.4.24, 8.5.0 - 8.5.9
int(0) int(1)

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