Hearing one of the core engineers from the LLVM compiler team speak at some length about their aims and approach to Swift, it was cleat that they had reflected long and hard on the approaches of many other languages. This engineer had very informed and nuanced views on the strengths and weaknesses of pretty much any other language you asked about. I'm sure Scala was on this list, also "Objective-C, Rust, Haskell, Ruby, Python, C#, CLU, and far too many others to list" — http://www.nondot.org/sabre/
