TAL Reference Manual

Statements
TAL Reference Manual—526371-001
12-20
DROP Statement
2. This DO statement loops through ARRAY_A, assigning a 0 to each element until all
the elements contain a 0:
LITERAL limit = 9;
INT index := 0;
STRING .array_a[0:limit]; !Declare array
DO !DO statement
BEGIN
array_a[index] := 0; !Compound statement to
index := index + 1; ! execute in DO loop
END
UNTIL index > limit; !Condition for ending loop
DROP Statement
The DROP statement disassociates an identifier from either:
•
A label
•
An index register that you reserved in a previous USE statement
identifier
is the identifier of either:
•
A label
•
An index register that you reserved in a previous USE statement
Usage Considerations
Following are guidelines for dropping labels and registers.
Dropping Labels
You can drop a label only if you have declared the label or used it to label a statement.
Before you drop a label, be sure there are no further references to the label. If a GOTO
statement refers to a dropped label, a run-time error occurs. After you drop a label, you
can, however, use the identifier to label a statement preceding the GOTO statement
that refers to the label.
DROP
identifier
,
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