How do I convert an Array[String] to a Set[String]?

scala scala-collections
dave4420 picture dave4420 · Apr 25, 2011 · Viewed 35.9k times · Source

I have an array of strings. What's the best way to turn it into an immutable set of strings?

I presume this is a single method call, but I can't find it in the scala docs.

I'm using scala 2.8.1.

Answer

tenshi picture tenshi · Apr 25, 2011

This method called toSet, e.g.:

scala> val arr = Array("a", "b", "c")
arr: Array[java.lang.String] = Array(a, b, c)

scala> arr.toSet
res1: scala.collection.immutable.Set[java.lang.String] = Set(a, b, c)

In this case toSet method does not exist for the Array. But there is an implicit conversion to ArrayOps.

In such cases I can advise you to look in Predef. Normally you should find some suitable implicit conversion there. genericArrayOps would be used in this case. genericWrapArray also can be used, but it has lower priority.

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