Scala: How to use function as a parameter?

Question

I have a function:

sigma(x: Int, y: Int, z: Int, a: Int)(f: (Int, Int, Int, Int) => Double): Double

I need to set it as a parameter of another function:

bigPi(x: Int, y: Int, z: Int, a: Int)('Here should be sigma'):Double

How to define a type of sigma correctly and use it as an argument of bigPi?

Note: those two are not functions. They are methods. Functions and methods are fundamentally different. — Jörg W Mittag
– Jörg W Mittag, Commented Nov 7, 2018 at 16:57

jwvh · Accepted Answer · 2018-11-07 10:32:10Z

3

def sigma(x:Int, y:Int, z:Int, a:Int)(f:(Int,Int,Int,Int) => Double):Double = 1.1

def bigPi(x: Int, y: Int, z: Int, a: Int)(
             f: (Int,Int,Int,Int) => ((Int,Int,Int,Int) => Double) => Double
         ):Double = 2.2

bigPi(1,2,3,4)(sigma)

The IntelliJ IDE says there are unnecessary parentheses but the compiler says otherwise.

answered Nov 7, 2018 at 10:32

jwvh

51.3k7 gold badges42 silver badges70 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

SCouto · Accepted Answer · 2018-11-07 10:34:04Z

1

Try this:

def bigPi(x: Int, y: Int, z: Int, a: Int)(s: (Int, Int, Int, Int) => ((Int, Int, Int, Int) => Double) => Double) = whatever

answered Nov 7, 2018 at 10:34

SCouto

7,9465 gold badges37 silver badges52 bronze badges

Collectives™ on Stack Overflow

Scala: How to use function as a parameter?

2 Answers 2

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related