Has anyone taken a look at the upcoming language Ceylon<http://in.relation.to/Tutorials/IntroductionToCeylon>? It feels to me like a pretty aggressively blub-y Java clone, but it has two features that seem like they're ripped straight out of Typed Racket.
It looks like the language includes a basically verbatim copy of TR's dotted type parameters, which it calls "sequenced type parameters<http://in.relation.to/Bloggers/IntroductionToCeylonPart8#H-RepresentingTheTypeOfAFunction>". For example, the supertype of all tuples is written Tuple<T,P...><http://in.relation.to/Bloggers/TuplesOrNot> . It also has untagged union types<http://in.relation.to/Bloggers/IntroductionToCeylonPart5>(written like Int|Bool) which can be deconstructed with switch-case statements, sort of like a watered down version of occurence typing: switch (foo) case (is Bool) { // this type checks local isTrue = foo || true; ... } case (is Int) { // so does this! local x = foo + 1; ... } Anyhow, I just thought it was interesting that a language positioning itself as the successor to Java has as its main point of difference two features that are almost identical to those in Typed Racket - type-safe untagged unions and non-uniform variable-arity polymorphism. Even though the actual language is pretty unappealing to me (and I suspect it might be to most people who frequent this mailing list) I thought this was a neat confirmation of the broad appeal of TR's ideas.
_________________________________________________ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/users
