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javascalasetcontains

With Scala's Set, is there a method analog to the containsAll method in Java's Set?

While working through converting some Java code over to Scala, I discovered while there is a contains method for Scala's Set, there isn't a containsAll method. Am I just missing the correct method name?

Here's a bit of code I worked up to fill in the gap so I could quickly get back to working. Is it sufficient, or am I missing some subtlety?

  def containsAll[A](set: Set[A], subset: Set[A]): Boolean =
    if (set.size >= subset.size)
      subset.forall(a => set.contains(a))
    else
      false
Solution

  • There is subsetOf, which tests whether or not the elements of a Set are contained within another Set. (Kind of the reverse in terms of the expression)

    val set = Set(1,2,3,4)
val subset = Set(1,2)

scala> subset.subsetOf(set)
res0: Boolean = true

scala> set.subsetOf(subset)
res1: Boolean = false