Editing Your Program; Erasing A Line From A Program; Duplicating A Line; Replacing A Line - Commodore 128 System Manual

Editing Your Program

The following paragraphs will help you to type in your programs
and make corrections and additions to them.

Erasing a Line from a Program

Use the LIST command to display the program you typed
previously. Now type 10 and press RETURN. You just erased line
10 from the program. LIST your program and see for yourself. If
the old line 10 is still on the screen, move the cursor up so that it
is blinking anywhere on that line. Now, if you press RETURN, line
10 is back in the computer's memory.

Duplicating a Line

Hold down the SHIFT key and press the CLR/HOME key on the
upper right side of your keyboard. This will clear your screen.
Now LIST your program. Move the cursor up again so that it is
blinking on the "0 " in the line numbered 10. Now type a 5 and
press RETURN. You have just duplicated (i.e., copied) line 10.
The duplicate line is numbered 15. Type LIST and press RETURN
to see the program with the duplicated lines.

Replacing a Line

You can replace a whole line by typing in the old line number
followed by the text of the new line, then pressing RETURN. The
old version of the line will be erased from memory and replaced
by the new line as soon as you press RETURN.

Changing a Line

Suppose you want to add something in the middle of a line.
Simply move the cursor to the character or space that
immediately follows the spot where you want to insert the new
material. Then hold down the SHIFT key and the INST/DEL key
together until there is enough space to insert your new
characters.
Try this example. Clear the computer's memory by typing NEW
and pressing RETURN. Then type:
10 ? " MY 128 IS GREAT"
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