Commodore Plus 4 - CHAPTER 5 Numbers and Calculations

your program as it is stored in the computer's memory When you
LIST a program, all lines appear in correct order and the replaced
lines don't appear:
LIST RETURN
—
The screen reads:
10 COLOR 0,3
20 PRINT "PLUS/4"
Replacing lines in a program is also a good way to experiment with
your computer. When you replace a line, the new one doesn't have
to be anything like the old line. For example, instead of correcting
the spelling of COLOR, you can type this:
. space
10 PRINT "TEN IS SIX "
RETURN —
Now RUN the program and see what happens.
2 YOU CAN ERASE AN UNWANTED LINE just by typing the
number of the line and pressing return .The computer
ignores the line even though it still appears on the screen.
Type LIST to get the program LISTing to make sure the line
is gone from the program.
10 PRINT "TEN IS SIX" RETURN
20 PRINT "PLUS/4" RETURN
10 RETURN
LIST RETURN
20 PRINT "PLUS/411
u
3 YOU CAN EDIT A LINE. Use the cursor keys to move to the place in
the line that you want to change. Now just type over what you want —
to change. Press return when you finish.
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