Commodore Plus 4 - Page 172

160 Some Programming Techniques
the output of the execution of the program is inserted above the old data. The old
data are pushed ahead of the execution output.
Canceling Automatic Insert Mode
Cancel automatic insert mode by pressing the ESCape key and then the C key. As
soon as you issue this key sequence, normal conditions return. Note that ESCape
O cancels manual insert mode but not automatic insert mode.
Deleting the Current Line
The ESCape D function lets you erase a line on the screen. To use ESCape D,
move the cursor to the line you want to erase; then press the ESCape key and then
the D key. The current line is deleted, and any following lines are moved up one
line to fill in the gap. You can erase additional lines by repeating the key sequence.
If the line is part of a BASIC line that is longer than one screen line, the entire
BASIC line is deleted from the screen display.
The ESCape D function edits only what is on the screen, not what is in the
program area of memory. This means that lines deleted by the ESCape D
sequence are erased from the screen but not from the program. If you LIST the
program after you use ESCape D to delete a line, you will see that the line is still in
the program. You can use the DELETE command to remove a line from a
program.
Inserting a Blank Line
The ESCape I function lets you insert a blank line between two lines anywhere on
the screen. To use ESCape I, move the cursor to the line where you want to insert
a blank line; then press the ESCape key and then the I key. A blank line is
inserted, and any following lines are moved down one line to make room for the
new line. You can add additional blank lines by repeating the key sequence.
Erasing Partial Lines
ESCape P and ESCape Q erase partial lines. ESCape P erases all characters that
precede the cursor and the character under the cursor. ESCape Q erases all
characters that follow the cursor and the character under the cursor. The cursor
does not move when you execute either of these sequences.
If you are using ESCape P or ESCape Q to erase part of a program line and