This is a small Scala tutorial exercise to start getting used to the syntax of Scala programming.

It is typically taken before introducing functional programming concepts, so students should feel free to just use imperative programming to complete this tutorial.

The project is organised as an sbt project: src/main/scala contains the main code and src/test/scala contains tests that will be run against it if you run sbt test (or test from an interactive sbt prompt).

A few language conventions are useful to remember before you begin the tutorial:

Scala compiles (by default) to run on the JVM. Just as Java requires a little overhead to define a program, so does Scala. So, this in Java

public class MyApp {

    public static void main(String[] args) {
        // program
    }
}

might be replaced by this in Scala:

object MyApp {

    def main(args:Array[String]) = {
        // program
    }

}

Notice that in Java, main is a static method on a class. In Scala, each class can have a "companion object" - a single object with the same name as the class. Methods defined on a companion object are (roughly) similar to static methods in Java.

If you open src/main/scala/cosc250/firststeps/StepOne.scala you'll notice there is an object containing the code, and a 'main' method.

The first exercises ask you to run the object. To run the object, from the sbt interactive prompt, run the command run.

The next exercises ask you to run the tests. To run the tests, from the sbt interactive prompt, run the command test.

In this case, the test framework is the program that is run, and it runs the tests that are defined in src/test/scala/cosc250/firststeps/FirststepsSpec.scala. So, in this case, the testing framework is providing the main method.

Remember, though, that if there is a compile error in your code, even if it is in a different part of the code than you want to test right now, the code won't compile and the tests can't run.

Open the project in your favourite IDE, and start an sbt shell. The exercises are in StepOne.scala and the comments provide additional instructions. Your task is to edit the code to make the tests pass.