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<?php var_dump(@hello); function atom(...$atoms) { array_walk( $atoms, function ($atom) { if (defined($atom)) { if ($atom !== constant($atom)) raise("The atom is already defined with a different value: ".$atom); } else { define($atom, $atom); } } ); } atom(@atom); atom(@raise); atom(@dispatch); atom(@acceptsmessage); atom(@isatom); var_dump(@atom);
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
Fatal error: Uncaught Error: Undefined constant "hello" in /in/sMAiv:2 Stack trace: #0 {main} thrown in /in/sMAiv on line 2
Process exited with code 255.
Output for 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 - 7.3.33, 7.4.0 - 7.4.33
string(5) "hello" string(4) "atom"
Output for 5.5.0 - 5.5.38
Parse error: syntax error, unexpected '.', expecting '&' or variable (T_VARIABLE) in /in/sMAiv on line 3
Process exited with code 255.

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