__FB_IIF__keyword

Intrinsic define (macro) performed by the compiler.

Syntax

__FB_IIF__( compare-expr, true-expr, false-expr )

Parameters

Name		Description
`compare-expr`		The comparison expression to test. A non-zero value evaluates as true, while a value of zero evaluates as false.
`true-expr`		Source code to return if
`compare-expr`		is true.
`false-expr`		Source code to return if
`compare-expr`		is false.

Description

__FB_IIF__ returns source code text depending on the result of a comparison expression evaluated at preprocessing-time.
Its typical use is in the middle of an expression; it avoids splitting it to put a conditional in the middle.

This intrinsic define (macro) differs from the IIf conditional statement in that __FB_IIF__ is evaluated at compile-time only and returns source code text. IIf is evaluated at compile-time only if the compare-expr is a constant. Otherwise IIf expressions are evaluated at run-time.

Remarks

Version

Since fbc 1.10.0

Differences from QB

New to FreeBASIC

Example

' From the example of the '#ELSE' documentation page:

    '#DEFINE MODULE_VERSION 1

    'Dim a As String

    '#IF (MODULE_VERSION > 0)

    '    a = "Release"

    '#ELSE

    '    a = "Beta"

    '#ENDIF

    'Print "Program is "; a



' Simpler code using '__FB_IIF__':

    #define MODULE_VERSION 1

    Dim a As String

    a = __FB_IIF__( MODULE_VERSION > 0, "Release", "Beta" )

    Print "Program is "; a

Reference

Documented in KeyPgDdfbiif.html