start.index
[integer] Start byte index of the logical range. If this value
is less than the start index for the line, then
the first range will extend all the way to the leading
edge of the layout. Otherwise it will start at the
leading edge of the first character.
end.index
[integer] Ending byte index of the logical range. If this value
is greater than the end index for the line, then
the last range will extend all the way to the trailing
edge of the layout. Otherwise, it will end at the
trailing edge of the last character.