Steps

1. How to initialize a Sequence of donuts

The code below shows how to initialize a sequence of donut elements where each element in the sequence is of type String.

println("Step 1: How to initialize a Sequence of donuts")
val donuts: Seq[String] = Seq("Plain Donut", "Strawberry Donut", "Glazed Donut")
println(s"Elements of donuts = $donuts")

You should see the following output when you run your Scala application in IntelliJ:

Step 1: How to initialize a Sequence of donuts
Elements of donuts = List(Plain Donut, Strawberry Donut, Glazed Donut)

2. How to access the first element of the donut sequence

The code below shows how to access the first element in the donut sequence by using the zero index.

println("\nStep 2: How to access the first element of the donut sequence")
println(s"First element of donut sequence = ${donuts(0)}")

You should see the following output when you run your Scala application in IntelliJ:

Step 2: How to access the first element of the donut sequence
First element of donut sequence = Plain Donut

3. How to access the first element of the donut sequence using the head method

The code below shows how to use the head method to access the first element of the donut sequence.

println("\nStep 3: How to access the first element of the donut sequence using the head method")
println(s"First element of donut sequence using head method = ${donuts.head}")

You should see the following output when you run your Scala application in IntelliJ:

Step 3: How to access the first element of the donut sequence using the head method
First element of donut sequence using head method = Plain Donut

4. How to create an empty sequence

The code below shows how to represent an empty donut sequence by creating an empty sequence of type String.

println("\nStep 4: How to create an empty sequence")
val donuts2: Seq[String] = Seq.empty[String]
println(s"Elements of donuts2 = $donuts2")

You should see the following output when you run your Scala application in IntelliJ:

Step 4: How to create an empty sequence
Elements of donuts2 = List()

5. How to access the first element of the donut sequence using the headOption function

The code below shows how to use the headOption method to access the first element of an empty sequence in order to avoid unnecessary runtime exceptions on empty sequences.

println("\nStep 5: How to access the first element of the donut sequence using the headOption function")
println(s"First element of empty sequence = ${donuts2.headOption.getOrElse("No donut was found!")}")

You should see the following output when you run your Scala application in IntelliJ:

Step 5: How to access the first element of the donut sequence using the headOption function
First element of empty sequence = No donut was found!

NOTE:

• We also made use of the getOrElse() method which you can review from the tutorial on Option, Some and None.