Discussion on: Look ma', without loops!

[Ben Sinclair]

What happens when there are no students in the class that term?

[Christian Vasquez]

As it is right now, when the calculateAverageScore() function gets executed, since the students.size is zero, it will cause a java.lang.ArithmeticException: / by zero 💥

[Valeriy Zhirnov]

To avoid this you can use average function from stdlib, so istead of this:

fun calculateAverageScore(students: Array<Student>) = 
        students.sumBy { it.score } / students.size

You can write:

fun calculateAverageScore(students: Array<Student>) = 
        students.map { it.score }.average()