original_string: protected function keygen($length)
      {
          $key = '';
          for($i = 1; $i < $length; $i++) {
              $key .= mt_rand(0,9);
          }
          $key .= mt_rand(1,9);
          
          return $key;
      }
code: protected function keygen($length)
      {
          $key = '';
          for($i = 1; $i < $length; $i++) {
              $key .= mt_rand(0,9);
          }
          $key .= mt_rand(1,9);
          
          return $key;
      }
code_tokens: protected function keygen ( $ length ) { $ key = '' ; for ( $ i = 1 ; $ i < $ length ; $ i ++ ) { $ key .= mt_rand ( 0 , 9 ) ; } $ key .= mt_rand ( 1 , 9 ) ; return $ key ; }
docstring: Generates a private key.
  @param int $length Length of the key.
docstring_tokens: Generates a private key .