From the article:

    val x = new Array[Integer](3)  //type inferred for x
    x(0) = 1
    x(1) = 2
    x(2) = 3
    
    for (y <- x if y > 2)
        println(y)

The idiomatic way to do this is:

    val x = Array(1, 2, 3)

That infers the type and sets values in one shot, with fewer characters. Also, using Integer (that's the java.lang.Integer) has been deprecated since 2.8.1 I believe. `Int` is preferred unless you really mean to use `Integer` (e.g. you're using a native Java library).