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<?php $fields = [ 'email' => '', 'gender' => '', 'birthday' => '', 'name' => '', 'country_code' => '', 'city' => '', 'photo' => '', 'created_at' => '', 'project' => '', ]; echo implode(',',array_map(function($f){return ':'.$f;}, array_keys($fields))); var_dump($fields);
Output for 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, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
:email,:gender,:birthday,:name,:country_code,:city,:photo,:created_at,:projectarray(9) { ["email"]=> string(0) "" ["gender"]=> string(0) "" ["birthday"]=> string(0) "" ["name"]=> string(0) "" ["country_code"]=> string(0) "" ["city"]=> string(0) "" ["photo"]=> string(0) "" ["created_at"]=> string(0) "" ["project"]=> string(0) "" }
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29
Parse error: syntax error, unexpected '[' in /in/XdIXv on line 3
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 '[' in /in/XdIXv on line 3
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error in /in/XdIXv on line 3
Process exited with code 255.

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