The %ifdef directive – HP SunSoft Pascal 4.0 User Manual

Page 282

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258

Pascal 4.0 User’s Guide

A

Comments

When

pc

encounters a

%if

directive, it evaluates expression. If expression is

true

,

pc

executes the statements in the

%then

part. If expression is

false

,

pc

skips over the

%then

part and executes the

%else

,

%elseif

, or

%endif

directive. If no such directive exists,

pc

proceeds to the next statement.

The expression consists of a conditional variable and the optional

boolean

operators

and

,

or

, and

not

. You can set a conditional variable on the

command-line by using the

-config

option. See “–config” on page 27 for

information on this option.

Assuming

one

and

two

are conditional variables, expression can be any of the

following:

one

two

one and two

one or two

not one

not two

Example

See the example in the

%else

listing on page 250.

The

%ifdef

Directive

The

%ifdef

directive determines whether or not you previously defined a

conditional variable in a

%var

directive.

Syntax

%ifdef

expression

%then

.

.

%elseifdef

expression

%then

.

.

%endif

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