Using case and where statements with conditional statements and loops

As we saw with switch statements, the case and where statements within a switch statement can be very powerful. Using case and where statements within our conditional statements can also make our code much smaller and easier to read. Conditional statements and loops, such as if, for, and while, can also make use of the where and case keywords. Let's take a look at some examples, starting off with using the where statement to filter the results in a for-in loop.

Filtering with the where statement

In this example, we take an array of integers and print out only multiples of 3. However, before we look at how to filter the results with the where statement, let's take a look at how to do this without the where statement:

for number in 1...30 { 
    if number % 3 == 0 {
        print(number)
    }
}

In this example, we use a for-in loop to cycle through the numbers 1 to 30. Within the for-in...