Scala: Taking an array with one function inside as an argument

Question

I'm trying to define an array of numbers with the last being a function. It'll probably be better to give an example:

def myArrayFunc(foo:String, bar:Array[Int[Function1]]) // ?
myArrayFunc("foo", (1,2,3 (myFunction)))

Is this possible using Scala? If so, how?

Thanks in advance.

score 2 · Accepted Answer · answered May 05 '14 at 23:47

Your question as stated is nonsensical, because a function is not a number. But if you meant an array of numbers and also a function, then you can do:

def myArrayFunc(foo:String, bar: Array[Either[Int, Function1[A, B]]])

or if you prefer efficiency over type safety:

def myArrayFunc(foo:String, bar: Array[Any])

But it would really make more sense to do:

def myArrayFunc(foo:String, bar: Array[Int], f: Function1[A, B])

Replace A and B with appropriate types in the above.

score 1 · Answer 2 · edited May 23 '17 at 12:20

1

Yes it is possible but you cannot use an Array; you need something like a Vector. This is further answered here: How do I create a heterogeneous Array in Scala?

edited May 23 '17 at 12:20

Community

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answered May 05 '14 at 23:34

Anthony G

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`Array` works perfectly fine: `val a = Array(1, 2, (x: Int) => x)`. The accepted linked answer is wrong. – wingedsubmariner May 05 '14 at 23:52

score 0 · Answer 3 · answered May 05 '14 at 23:01

You can define Array[Int] with an element that is a function as long as the function returns an Int since all elements in a Scala Array must have the same type.

def myArrayFunc(foo:String, bar:Array[Int]) = bar.map(_ + foo) 

scala> def plusOne(i:Int) = i + 1
plusOne: (i: Int)Int

scala> myArrayFunc("foo", Array(1,2,plusOne(2)))
res22: Array[String] = Array(1foo, 2foo, 3foo)

Scala: Taking an array with one function inside as an argument

3 Answers3