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<?php function fromCamelCaseToUnderscores($str) { $str[0] = strtolower($str[0]); // Just in case first character is uppercase. $str = str_replace('ID', 'Id', $str); // Hack for the way CATS defies camelCase convention return preg_replace_callback('/([A-Z])/', function($char) { return '_' . strtolower($char[1]); }, $str); } var_dump(fromCamelCaseToUnderscores(null));
Output for git.master, git.master_jit
Warning: Trying to access array offset on value of type null in /in/o50mS on line 5 Deprecated: strtolower(): Passing null to parameter #1 ($string) of type string is deprecated in /in/o50mS on line 5 array(1) { [0]=> string(0) "" }
Output for rfc.property-hooks
Warning: Trying to access array offset on null in /in/o50mS on line 5 Deprecated: strtolower(): Passing null to parameter #1 ($string) of type string is deprecated in /in/o50mS on line 5 array(1) { [0]=> string(0) "" }

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