pTAL Conversion Guide

Statements

pTAL Conversion Guide—527302-002

15-16

IF Statement

The IF statement conditionally selects one of two statements to execute.

Topics:

•

Testing Address Types on page 15-16

•

Testing Hardware Indicators on page 15-16

•

Testing INT(32) Variables Without a Not-Equal Operator on page 15-16

Testing Address Types

In both TAL and pTAL, an IF statement can test any 16-bit compatible value—INT,

STRING, or UNSIGNED(1-16)—as if it were a Boolean value. The result of evaluating

an IF statement’s conditional expression must yield a 16-bit result. Valid conditional

expressions are described in Relational Operators and Condition Codes on

page 13-10.

In pTAL, an IF statement can test an EXTADDR variable as if it were a Boolean value.

Testing Hardware Indicators

Native architecture does not have the hardware indicators that TNS architecture does.

Instead, the native compiler emits code that supports the hardware indicators. For

more information, see Section 20, Hardware Indicators.

Testing INT(32) Variables Without a Not-Equal Operator

TAL

You can test an INT variable for a nonzero value without specifying a not-equal

operator; however, the variable tested by the IF statement cannot be an INT(32)

variable.

pTAL

You can also test an INT(32) variable for a nonzero value without specifying the not-

equal operator.

Example 15-21. Testing an INT Variable Without a Not-Equal Operator (TAL)

INT i;

...

IF i THEN... ! OK: same as "IF i <> 0 THEN ..."