This month saw some exciting hints from the Scala mailing list, and LtU, about GADTs in Haskell, in Scala, and perhaps eventually even in C#.
Martin Odersky wrote that there would be support for GADT's in the new version of Scala. (The current compiler is written in a variant of Java; it is being rewritten in Scala itself.)
SPJ et al have rewritten the Wobbly Types paper, providing a simpler implementation and semantics for GADT's. GADT's revisited http://lambda-the-ultimate.org/node/view/1132
And LtU http://lambda-the-ultimate.org/node/view/1134
And the C# connection ...
Andrew Kennedy and Russo have a "GADTs and Object-Oriented Programming" paper; there's an abstract near the end of Kennedy's generics page, and a complete PDF version here. 11:56:47 PM comment/
Random radio Weblog