|  IF/THEN/ELSE Statement |
Reference/Commodore BASIC V3.5
IF expression THEN then-clause [:ELSE else-clause]
The IF/THEN statement analyses a BASIC expression, and takes different actions depending on whether the expression is true or false.
IF is followed by the expression, which can use any comparison operators (=, <, >, <>, <=, >=), and by using the AND, OR and NOT arguments, additional comparisons can be added.
The expression is followed by THEN. If the expression is true, the statements following THEN are executed, up to the end of that BASIC line. NOTE: If THEN is to be immediately followed by the GOTO statement, this can be expressed as either THEN line#, or GOTO line# (with the word GOTO in place of THEN).
If the IF expression is false, the statements following ELSE (if present) are executed instead. The ELSE clause must be in the same line as the IF statement. If there is no ELSE clause and the IF expression is false, program execution continues on the next line. If ELSE is to be immediately followed by GOTO line#, ELSE line# can be used instead.
IF A$="N" THEN PRINT"BYE":END Checks the value of A$. If A$ is "N" (making the expression true) then the statements following THEN are executed. Otherwise program execution continues on the next line
IF B=0 THEN 10
IF B=0 GOTO 10 Alternative ways of stating THEN GOTO 10
10 IF X>0 AND X<9 THEN PRINT X:GOTO 50:ELSE 5 If the expression is false, the statements following ELSE are executed. In this case, ELSE 5 is a shortened version of ELSE GOTO 5
IF: None
THEN: T SHIFT+H
ELSE: E SHIFT+L |
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