Use SelectExtend to select (or deselect) within the current session all eligible selection units between the previous ending selection point and the specified row and column. (See Selection.)
The SelectExtend command is used primarily in support of mouse selection.
SelectExtend may also be entered as SelectExt[end] or SelExt[End].
Optional Operands
ROW specifies the ending line number through which selection (or deselection) is to occur.
Default: Current ending selection row.
COL specifies the ending column through which selection (or deselection) is to occur.
Default: Current ending selection column.
Return Codes
OK Successful.
Examples
Extend the current selection through row 20, col 40:
=> selext 20,40