If one views the CLR/.NET runtime and associated libraries as the future of windows, then the F# programming language could be seen in that light as the most native functional language. Meaning that it has support from the OS creator, presumably integrates best with their libraries, etc.
Is there a similar logical choice of language on the Mac OS X platform? While the most-native language itself is obviously Objective-C, is there a first-among-equals or most obvious functional paradigm language that stands out?
Best Answer
Objective-C, as has been said, is the lingua franca for Mac development, if you want to hook in with Cocoa easily. That said, the best alternative language for Cocoa development is probably MacRuby, which is a Ruby implemented in Obj-C and can directly interface with Cocoa. It's not a functional language, it has some functional constructs. It's sorta developed by Apple (open sourced from Apple).
If you want a functional language for Mac OSX development, I think the best choice is Nu, which is a sorta-Lisp dialect built in Obj-C and can hook directly into Cocoa. It's not like F# (supported by the OS creator), but it is actively developed.