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<?php $boo = 1; $_SESSION['boo']='$boo'; $boo = 2; echo 'boo = ', $boo; echo '$_SESSION[boo] = ', "${$_SESSION[boo]}";
Output for 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
Deprecated: Using ${expr} (variable variables) in strings is deprecated, use {${expr}} instead in /in/4uFHG on line 6 boo = 2$_SESSION[boo] = Fatal error: Uncaught Error: Undefined constant "boo" in /in/4uFHG:6 Stack trace: #0 {main} thrown in /in/4uFHG on line 6
Process exited with code 255.
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.27
boo = 2$_SESSION[boo] = Fatal error: Uncaught Error: Undefined constant "boo" in /in/4uFHG:6 Stack trace: #0 {main} thrown in /in/4uFHG on line 6
Process exited with code 255.
Output for 7.2.0 - 7.2.33, 7.3.16 - 7.3.31, 7.4.0 - 7.4.33
boo = 2$_SESSION[boo] = Warning: Use of undefined constant boo - assumed 'boo' (this will throw an Error in a future version of PHP) in /in/4uFHG on line 6 Notice: Undefined variable: $boo in /in/4uFHG on line 6
Output for 7.3.32 - 7.3.33
boo = 2$_SESSION[boo] = Warning: Use of undefined constant boo - assumed 'boo' (this will throw an Error in a future version of PHP) in /in/4uFHG on line 6
Output for 5.4.1 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.20
boo = 2$_SESSION[boo] = Notice: Use of undefined constant boo - assumed 'boo' in /in/4uFHG on line 6 Notice: Undefined variable: $boo in /in/4uFHG on line 6

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