Take a detailed look at implementation of isSorted function, what would be the result of applying the following anonymous function with array to it?
``````
def isSorted[A](as: Array[A], ordering: (A, A) => Boolean): Boolean = {
@annotation.tailrec
def go(n: Int): Boolean =
if (n >= as.length - 1) true
else if (ordering(as(n), as(n + 1))) false
else go(n + 1)

go(0)
}

isSorted(Array(1, 3, 5, 7), (x: Int, y: Int) => x > y)
``````
Explanation
Let’s look how the function is executed step-by-step:
``````n == 0

ordering(as(0), as(1)) ==
ordering(1, 3) ==
(1 > 3) ==
false

n == 1

ordering(as(1), as(2)) ==
ordering(3, 5) ==
(3 > 5) ==
false

n == 2

ordering(as(2), as(3)) ==
ordering(5, 7) ==
(5 > 7) ==
false

n == 3

(n >= as.length - 1) == (n == 3) == true

``````
Source: Scala Exercises: getting started with functional programming
Theory
• Higher-order Functions
Scala allows the definition of higher-order functions. These are functions that take other functions as parameters, or whose result is a function. Here is a function apply which takes another function f and a value v and applies function f to v:
``def apply(f: Int => String, v: Int) = f(v)``
Note: methods are automatically coerced to functions if the context requires this.