Iterate Over a tuple

Question

I need to implement a generic method that takes a tuple and returns a Map Example :

val tuple=((1,2),((\"A\",\"B\"),(\"C\",3)),4)

I have b

Answer 1

What about? :

def flatProduct(t: Product): Iterator[Any] = t.productIterator.flatMap {
  case p: Product => flatProduct(p)
  case x => Iterator(x)
}
val tuple = ((1,2),(("A","B"),("C",3)),4)
flatProduct(tuple).mkString(",") // 1,2,A,B,C,3,4

Ok, the Any-problem remains. At least that´s due to the return type of productIterator.

Answer 2

tuple.productIterator map { 
   case (a,b) => println(a,b) 
   case (a) => println(a)
}

Answer 3

This works for me. tranform is a tuple consists of dataframes

def apply_function(a: DataFrame) = a.write.format("parquet").save("..." + a + ".parquet")
transform.productIterator.map(_.asInstanceOf[DataFrame]).foreach(a => apply_function(a))

Answer 4

Instead of tuples, use Shapeless data structures like HList. You can have generic processing, and also don't lose type information.

The only problem is that documentation isn't very comprehensive.