Consider this code:
if System.IsFunctionAvailable( "backingScaleFactor", "AppKit" ) then
soft declare function BackingScaleFactor lib "AppKit" selector "backingScaleFactor" (target As WindowPtr) as double
// Introduced in MacOS X 10.7.
r = BackingScaleFactor(w)
end if
The declare itself works, but IsFunctionAvailable returns false. Why?