Are there any methods included in Scala to convert tuples to lists?
I have a Tuple2
of List[List[String]]
and I'd like to be able to convert the tuple to a list so that I can then use List.transpose()
. Is there any way to do this? Also, I know it's a Pair
, though I'm always a fan of 开发者_运维知识库generic solutions.
Works with any tuple (scala 2.8):
myTuple.productIterator.toList
Scala 2.7:
(0 to (myTuple.productArity-1)).map(myTuple.productElement(_)).toList
Not sure how to maintain type info for a general Product or Tuple, but for Tuple2:
def tuple2ToList[T](t: (T,T)): List[T] = List(t._1, t._2)
You could, of course, define similar type-safe conversions for all the Tuples (up to 22).
Using Shapeless -
@ import syntax.std.tuple._
import syntax.std.tuple._
@ (1,2,3).toList
res21: List[Int] = List(1, 2, 3)
@ (1,2,3,4,3,3,3,3,3,3,3).toList
res22: List[Int] = List(1, 2, 3, 4, 3, 3, 3, 3, 3, 3, 3)
Note that type information is not lost using Shapeless's toList
.
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