Re: [hoc-users] performSelectorWithObject problems

[Wolfgang T. <wol...@gm...>]

> There's just one problem left: When I demand the state of a button,  
> it returns an IO Int, the according constants are of type  
> NSCellStateValue. Is there a way to "cast" those values?

The InterfaceGenerator generates the following:

data NSCellStateValue = NSMixedState
                       | NSOffState
                       | NSOnState
instance ObjCArgument NSCellStateValue CInt where
     exportArgument NSMixedState = return (-1)
     exportArgument NSOffState = return 0
     exportArgument NSOnState = return 1
     importArgument (-1) = return NSMixedState
     importArgument 0 = return NSOffState
     importArgument 1 = return NSOnState
     objCTypeString _ = "i"

You can use those, but it is obviously necessary to design something  
"proper".
Haskell's Enum class would not be appropriate because the succ, pred,  
enumFromTo, etc. functions aren't appropriate for everything that is  
defined using C enum.
And while we're at it, there's the question of what to do with  
anonymous enums (I'm just ignoring them so far).

Cheers,

Wolfgang