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<?php const CONFIG = [ 'pdo' = new PDO() ]; CONFIG['pdo'];
Output for 5.5.24 - 5.5.30, 5.6.8 - 5.6.16, 7.0.0
Parse error: syntax error, unexpected '=', expecting ']' in /in/CKoCQ on line 4
Process exited with code 255.

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