code: function (value, length) {
              value = String(value);
              var numMissing = length - value.length;
              var prefix = "";
              while (numMissing > 0) {
                  prefix += "0";
                  numMissing -= 1;
              }
              return prefix + value;
          }
docs: Pad a value by prepending zeroes until it reaches a specified length.
  
  @param {String} value the current string or number.
  @param {Number} length the size wanted for the value.
  @return {String} a string of at least the provided length.
  @api private
  
  @example zeroPad(50, 4) == "0050"
  @example zeroPad("123", 4) == "0123"