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Chapter 1: BASIC’s Basics
 
FRE
Use
FRE is a function which returns the amount of unused memory.
Syntax
FRE
 
CLEAR
Use
CLEAR discards all variables.
Syntax
CLEAR
Note
CLEAR may only be in Direct Mode.
Typing commands directly

Commands which you type directly into the Dialogue window are executed as soon an you press . Any output from these commands will appear in the Results-1 window, by default. Try this, if you like, by experimenting with simple commands like

print pi
birdcount = 24
print "There are"; birdcount ; "blackbirds in a" ; pi

In this way you can use the Dialogue window like a calculator. Notice, incidentally, that as soon as any variables are assigned, the variable space is no longer ‘clear’ and so the information line changes from Direct Comnand; Clear to Direct Command.

Unlike some BASICs, you cannot write a program by typing numbered statements in this way: programs have to be typed and edited in the Edit window.

Once a program has been written, though, you can use the Dialogue window to examine the value of the program’s variables after it has finished running, or while it is temporarily stopped in the middle of a run. This is an important technique for debugging, and it will be explained in Chapter 4 of this part of the manual.
BASIC 2 Plus: User Guide & Quick Reference 3

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