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<?php function normalizeHeaders(&$headers) { // Normalize headers array_walk( $headers, function (&$val, &$key) { $key = ucfirst(strtolower($key)); $val = ucfirst(strtolower($key)) . ': ' . $val; } ); } $headers = array('foo' => 'bar'); normalizeHeaders($headers); var_dump($headers);
Output for 8.2.0 - 8.2.18, 8.3.0 - 8.3.7
Warning: {closure}(): Argument #2 ($key) must be passed by reference, value given in /in/V8SRv on line 6 array(1) { ["foo"]=> string(8) "Foo: bar" }
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.28
Warning: {closure}(): Argument #2 ($key) must be passed by reference, value given in /in/V8SRv on line 11 array(1) { ["foo"]=> string(8) "Foo: bar" }
Output for 5.3.0 - 5.3.29, 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, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33
array(1) { ["foo"]=> string(8) "Foo: bar" }
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17
Parse error: syntax error, unexpected T_FUNCTION in /in/V8SRv on line 8
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 T_FUNCTION in /in/V8SRv on line 8
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error in /in/V8SRv on line 8
Process exited with code 255.

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