Scrap Your Boilerplate equivalent in Scala?

Haskell has this cool generic traversal stuff that lets you call something like `map` on every node in a collection, either bottom-up or top-down. It's called `everywhere` and you'd do something like `everywhere f tree` and `f` would be called on every node in your tree. Writing something equivalent in Scala for `Traversable` is easy, but Haskell's also works on tuples and the equivalent of case classes or, more generically, what Scala calls `Product`s. You can traverse over the elements in a `Product` using the `productIterator` method, but is there some easy way to put a tuple or a case class back together once you know what the arguments to the constructor (actually, I guess the `apply` method) should be? ``` def mapOnProduct[X](f: X -> X, prod: Product) { val newArgs = prod.productIterator.map { case x: X => f(x) case id => id }.toList [?].apply(newArgs: _*) } ``` What can I replace `[?]` with so that this has some chance of working? Thanks!