// *_rows are column vectors for the orig column and the final column.
// row >= 0: an indix of the $orig or $final array
// row < 0: a blank row for that column
list($orig_matches, $final_matches, $orig_rows, $final_rows) = $this->interleave_changed_lines( $orig, $final );
// *_rows are column vectors for the orig column and the final column.
// row >= 0: an indix of the $orig or $final array
// row < 0: a blank row for that column
list($orig_matches, $final_matches, $orig_rows, $final_rows) = $this->interleave_changed_lines( $orig, $final );