How to convert a Seq[A] to a Map[Int, A] using a value of A as the key in the map?

Question

I have a Seq containing objects of a class that looks like this:

class A (val key: Int, ...)

Now I want to convert this Seq<

Answer 1

Map over your Seq and produce a sequence of tuples. Then use those tuples to create a Map. Works in all versions of Scala.

val map = Map(seq map { a => a.key -> a }: _*)