docs: function(maxLen) {
          // nearest power of 10 lower than maxLen
          var digits = parseInt(Math.log(maxLen) / Math.log(10));
          var pow10 = Math.pow(10, digits);
          
          // ok, find first character
          var firstChar = parseInt(maxLen / pow10);
  
          // right, put it into the correct bracket
          var barLen;
          if(firstChar > 5) {
              barLen = 5;
          } else if(firstChar > 2) {
              barLen = 2;
          } else {
              barLen = 1;
          }
  
          // scale it up the correct power of 10
          return barLen * pow10;
      }