fun main() {
    val i = 2
    print("Write $i as ")
    when (i) {
        1 -> println("one")
        2 -> println("two")
        3 -> println("three")
    }

    // You can use commas to separate multiple expressions in the same case statement.
    // We use the optional `else` case in this example as well.
    when(Calendar.getInstance().get(Calendar.DAY_OF_WEEK)) {
        Calendar.SATURDAY, Calendar.SUNDAY -> println("It's the weekend")
        else -> println("It's a weekday")
    }
    
    // `when` without an argument is an alternate way to express if/else logic.
    // Here we also show how the `case` expressions can be non-constants.
    val t = Calendar.getInstance()
    when {
        t.get(Calendar.HOUR_OF_DAY) < 12 -> println("It's before noon")
        else -> println("It's after noon")
    }
    
    // A type `when` can be used to compare types instead of values.
    // This can be useful to discover the type of a variable. In this example, the
    // variable `i` will have the type corresponding to its clause.
    fun whatAmI(i: Any) {
        when (i) {
            is Boolean -> println("I'm a bool")
            is Int -> println("I'm an int")
            else -> println("Don't know type ${i::class.simpleName}")
        }
    }
    
    whatAmI(true)
    whatAmI(1)
    whatAmI("hey")
}