Varargs to tuple in scala

Question

I'm pretty new to scala programming and would like to write a function returning a tuple instance by the arguments passed in. Here is what I mean:

def toTuple(strings : String*) = {
   //some code to create a tuple, if possible
   //the tuple should be consistent with the order the arguments were passed in
}

Is it possible to do so in scala?

See the linked question, but to better help, what to you want to achieve in the end / what is your idea behind it? — Elmar Weber, Jul 18 '15 at 11:37
@ElmarWeber There's no idea behind it, I'm simply learning scala and trying diffenret examples. — stella, Jul 18 '15 at 11:46
For historical reasons it's hard to abstract over scala tuples (this will be fixed in an upcoming version but that's probably a few years in the future). In general if you want to work generically it's better to use shapeless `HList`s. — lmm, Jul 20 '15 at 09:05

score 1 · Accepted Answer · answered Jul 18 '15 at 10:34

The problem is with returning type of this function. What should it be? Any? But that doesn't sound like a good static typing. I suggest you to use something like that:

def toTuple(strings : String*): (String, String) = strings.toList match{
  case Nil => ("", "")
  case a :: Nil => (a, "")
  case a :: b :: xs => (a, b)
}

Usage:

scala> toTuple(List("a"): _*)
res2: (String, String) = (a,"")

scala> toTuple(List("a", "b"): _*)
res3: (String, String) = (a,b)

Varargs to tuple in scala

1 Answers1