code: function (start, length) {
              if (!start) {
                  start = 0;
              }
              var contents = this.getFileContents();
              if (null !== contents) {
                  var lines = (contents).split("\n");
  
                  // Get a subset of lines from $start to $end
                  if (length !== null) {
                      start = parseInt(start);
                      length = parseInt(length);
                      if (start < 0) {
                          start = 0;
                      }
  
                      if (length <= 0) {
                          throw new RangeError(
                              "length cannot be lower or equal to 0"
                          );
                      }
  
                      lines = lines.slice(start, start + length);
                  }
  
                  return lines;
              }
          }
docs: Returns the contents of the file for this frame as an
  array of lines, and optionally as a clamped range of lines.
  
  NOTE: lines are 0-indexed
  
  @throws RangeError if length is less than or equal to 0
  @param  start
  @param  length
  @returns {Array|undefined}