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<?php error_reporting(-1); $a = ["b" => 2]; print "notice: ".$a[b]."\n"; print "no notice: {$a[b]}";
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
Fatal error: Uncaught Error: Undefined constant "b" in /in/D6vMV:7 Stack trace: #0 {main} thrown in /in/D6vMV on line 7
Process exited with code 255.
Output for 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33
Warning: Use of undefined constant b - assumed 'b' (this will throw an Error in a future version of PHP) in /in/D6vMV on line 7 notice: 2 Warning: Use of undefined constant b - assumed 'b' (this will throw an Error in a future version of PHP) in /in/D6vMV on line 9 no notice: 2
Output for 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33
Notice: Use of undefined constant b - assumed 'b' in /in/D6vMV on line 7 notice: 2 Notice: Use of undefined constant b - assumed 'b' in /in/D6vMV on line 9 no notice: 2
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29
Parse error: syntax error, unexpected '[' in /in/D6vMV on line 5
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.3.11, 4.4.0 - 4.4.1, 5.0.0 - 5.0.5
Parse error: parse error, unexpected '[' in /in/D6vMV on line 5
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error in /in/D6vMV on line 5
Process exited with code 255.

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