TAL Reference Manual

Statements

TAL Reference Manual—526371-001

12-40

WHILE Statement

LITERAL len = 100;

INT .array [0:len - 1];

INT i;

FOR i := 0 TO len - 1 DO

array[i] := array[i] + 5; !Standard FOR loop

USE x; !Optimized FOR loop uses

FOR x := 0 to len - 1 DO ! an index register

array[x] := array[x] + 5;

DROP x; !Release the register

WHILE Statement

The WHILE statement is a pretest loop that repeatedly executes a statement while a

specified condition is true.

condition

is either:

•

A conditional expression

•

An INT arithmetic expression. If the result of the arithmetic expression is not 0,

condition is true. If the result is 0, condition is false.

statement

is any TAL statement.

Usage Considerations

The WHILE statement tests the condition before each iteration of the loop. If the

condition is false before the first iteration, the loop never executes. If the condition is

always true, the loop executes indefinitely unless a statement in the loop causes an

exit.

WHILE statement execution is shown in the

TAL Programmer’s Guide.

condition

WHILE

statement

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