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<?php error_reporting( E_ALL ); $in = array(); $foo = 'f1'; $bar = 'b1'; if ( ! isset( $in[$foo][$bar] ) ) { $in[$foo][$bar] = array(); } print_r( $in ); $ob = new stdClass(); if ( ! isset( $ob->$foo->$bar ) ) { $ob->$foo->$bar = array(); } print_r( $ob );
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
Array ( [f1] => Array ( [b1] => Array ( ) ) ) Fatal error: Uncaught Error: Attempt to assign property "b1" on null in /in/g4uvN:15 Stack trace: #0 {main} thrown in /in/g4uvN on line 15
Process exited with code 255.
Output for 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 7.2.17 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33
Array ( [f1] => Array ( [b1] => Array ( ) ) ) Warning: Creating default object from empty value in /in/g4uvN on line 15 stdClass Object ( [f1] => stdClass Object ( [b1] => Array ( ) ) )
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29
Array ( [f1] => Array ( [b1] => Array ( ) ) ) stdClass Object ( [f1] => stdClass Object ( [b1] => Array ( ) ) )

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