Atari XL User Manual

DECISIONS
Program Control 43
IF (condition) THEN (instruction) decides between
two actions. The condition after If' is usually a test
of a variable. There may be more than one
instruction after THEN, in which case colons (:)
must be used to separate them. The complete IF ...
THEN command must be in one line.
GOTO need not be included if it would be the only
command after THEN, but it must be if there is
another command before it:
100 IF ACE
1 THEN 20
but 100 IF ACE 2 THEN KING
7:GOTO 20
SUBROUTINES
Diversions from a program, using the commands
GOSUB and RETURN. GOSUB calls the
subroutine, and RETURN at the end of the
subroutine returns the computer to the instruction
after the GOSUB.
ON ... GOSUB and ON ... GOTO
Select a destination from a list:
ON P GOSUB X, Y, Z
causes a GOSUB to the P'th item in the list.
ON N GOTO A, B, C
This causes a jump to the N'th destination - if
there is an N'th item in the list.
END halts the running of a program.

Atari XL Specifications

General

Brand	Atari
Model	XL
Category	Desktop
Language	English