Commodore PET - Gosub; Goto

line
GOSUB
The GOSUB statement branches program control to specified line and
allows a return to the next statement following the
GOSUB calI.
Format:
GOSUB line
where:
is a numeric constant specifying the first line of
the subroutine.
No special entry to a subroutine
is needed. The program branches control ta
the subroutine after making an entry on the Stack
(see Chapter 6). The subroutine
must terminate
with a RETURN statement to return program control ta the state-
ment
following the GOSUB statement that activated the subroutine. The RETURN
removes the Stack entry. A subroutine may be called from many places in a pro-
gram. As many
as 26 subroutines may be nested (25 GOSUBs before the first
RETURN).
Example:
10 GOSUB 100
GOTO
The GOTO statement branches unconditionally to the specified line.
Format:
GO TO} .
GOTO Ilne
where:
line
Example:
10 GOTO 100
is a numeric constant specifying the line to be
branched
to.
GOTO executed in immediate mode branches to the specified line in the
stored program
without clearing the current variable values. GOTO cannot
reference immediate mode statements, since they
do not have line numbers.
IF . .. THEN
The IF ... THEN statement provides conditional execution of statements
based
on a relational expression.
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