__FB_IIF__
Intrinsic define (macro) performed by the compiler.
Syntax
`
__FB_IIF__( compare-expr, true-expr, false-expr )
`
Parameters
`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.
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
`
Version

- Since fbc 1.10.0

Differences from QB

- New to FreeBASIC

See also

- `#if`
- `#else`
- `#endif`