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<?php // Nope! You can't access config/foo yet, you're in the middle of defining an array. // This will cause an 'undefined index' notice $GLOBALS['config'] = [ 'foo' => 'bar', 'baz' => $GLOBALS['config']['foo'] ]; print_r($GLOBALS['config']); // This works =) $GLOBALS['config'] = [ 'foo' => 'bar' ]; $GLOBALS['config']['baz'] = $GLOBALS['config']['foo']; print_r($GLOBALS['config']);
Output for 8.3.0 - 8.3.7
Warning: Undefined global variable $config in /in/M7itf on line 7 Warning: Trying to access array offset on null in /in/M7itf on line 7 Array ( [foo] => bar [baz] => ) Array ( [foo] => bar [baz] => bar )
Output for 8.1.0 - 8.1.28, 8.2.0 - 8.2.19
Warning: Undefined global variable $config in /in/M7itf on line 7 Warning: Trying to access array offset on value of type null in /in/M7itf on line 7 Array ( [foo] => bar [baz] => ) Array ( [foo] => bar [baz] => bar )
Output for 8.0.0 - 8.0.30
Warning: Undefined array key "config" in /in/M7itf on line 7 Warning: Trying to access array offset on value of type null in /in/M7itf on line 7 Array ( [foo] => bar [baz] => ) Array ( [foo] => bar [baz] => bar )
Output for 7.4.0 - 7.4.33
Notice: Undefined index: config in /in/M7itf on line 7 Notice: Trying to access array offset on value of type null in /in/M7itf on line 7 Array ( [foo] => bar [baz] => ) Array ( [foo] => bar [baz] => bar )
Output for 7.3.32 - 7.3.33
Array ( [foo] => bar [baz] => ) Array ( [foo] => bar [baz] => bar )
Output for 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.31
Notice: Undefined index: config in /in/M7itf on line 7 Array ( [foo] => bar [baz] => ) Array ( [foo] => bar [baz] => bar )
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