Apple II manual Pstg$, Print A, A*2 LET Z=7 Print Z, Z-A, Reserved Words

Z1	ZIABCD (variable name too	long)
TP	TO (variable names cannot	be reserved words)
PSTG$	RGOTO (variable names cannot contain reserved words)
COUNT

ASSIGNING VARIABLES WITH A LET OR ASSIGNMENT STATEMENT

Besides having values assigned to variables with an input statement, you can also set the value of a variable with a LET or assignment statement.

Try the following examples:

A=5

PRINT A, A*2

510

LET Z=7

PRINT Z, Z-A

7 2

As you will notice from the examples, the "LET" is optional in an assignment statement.

BASIC "remembers" the values that have been assigned to variables using this type of statement. This "remembering" process uses space in the memory to store the data.

The values of variables are discarded (and the space in memory used to store them is released) when one of four conditions occur:

*A new line is typed into the program or an old line is deleted

*A CLEAR command is typed in

*A RUN command is typed in

*NEW is typed in

Another important fact is that if a variable is encountered in a formula before it is assigned a value, it is automatically assigned the value zero. Zero is then substituted as the value of the variable in the

particular formula. Try the example below:

PRINT Q;Q+2;Q*2 0 2 0

RESERVED WORDS

The words used as BASIC statements are "reserved" for this specific purpose. You cannot use these words as variable names or inside of any variable name. For instance, "FEND" would be illegal because "END" is a reserved word.

Table 206-1 is a list of the reserved words in BASIC.

Table 206-1. AIM 65 BASIC Reserved Words

ABS	FN	LIST	PRINT	SPC
AND	FOR	LOAD	POS	SQR
ASC	FRE	LOG	READ	STEP
ATN	GET	MID$	REM	STOP
CHR$	GOSUB	NEW	RESTORE	STR$
CLEAR	GOTO	NEXT	RETURN	TAB
CONT	IF	NOT	RIGHT$	TAN
COS	INPUT	NULL	RND	THEN
DATA	INT	ON	RUN	TO
DEF	LEFT$	OR	SAVE	USR
DIM	LEN	PEEK	SGN	VAL
END	LET	POKE	SIN	WAIT
EXP