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<?php class Foo { static $modeMapping = array( 'bar' => 'Exception' ); public static function testing() { if (isset( self::$modeMapping[$mode] ) ) { return new self::$modeMapping[$mode]( ); } } } var_dump( Foo::testing() );
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
Warning: Undefined variable $mode in /in/eY00J on line 6 NULL
Output for 5.4.2 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.10, 7.2.0 - 7.2.33, 7.3.16 - 7.3.31, 7.4.0 - 7.4.33
Notice: Undefined variable: mode in /in/eY00J on line 6 NULL
Output for 7.3.32 - 7.3.33
NULL

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