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<?php $x = [ 'PascalCase' => 'camelCase', 'PascalCase2' => 'camelCase2', ]; // Lets convert the PascalCase keys to camelCase $arr = array_combine( array_map(function($k) { return lcfirst($k); }, array_keys($x)), array_values($x) ); var_dump($arr);

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