Functional Scala Intro

type Calculo = (Int, Int) => Int

def soma: Calculo = (x: Int, y: Int) = x + y

def subtracao: Calculo = (x: Int, y: Int) = x - y

def calcular(x: Int, y: Int)(f: Calculo) = f(x, y)

calcular(1, 3)(soma) // 4
calcular(4, 2)(subtracao) // 2