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 -configoption. 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

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%elseifdef expression %then

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%endif

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Pascal 4.0 User’s Guide