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run code in 300+ PHP versions simultaneously
<?php class a { protected static $foo = array(); public static function foo(){ var_dump(self::$foo); } public static function bar(){ self::$foo[] = 'foo'; } } class b extends a{ public static function foo(){ self::$foo[] = 'bar'; } } a::foo(); a::bar(); a::foo(); b::bar(); a::foo();

preferences:
31.35 ms | 402 KiB | 5 Q