This document provides an overview of a Scala course session on getting up to speed with Scala. The session covers conditional expressions, the type hierarchy, loops, and pattern matching. It includes examples of if/else expressions, the different types of loops in Scala, and how to perform pattern matching on types, sequences, and tuples. The document also discusses setting up the development environment with JDK, sbt, and IntelliJ before creating a sample project.

1. Scala
Session 2

2. Course Contents
1. The Basics
2. Getting up to speed
3. Collections
4. Classes and Objects
5. Inheritance and Traits
6. Functional Programming

3. Today’s Session (Getting Up to Speed)
● Conditional Expressions
● Type Hierarchy
● Loops
● Pattern Matching

4. Environment Setup
- JDK
- sbt (build tool for Scala)
- Idea-Intellij

5. Sample Project
- Lets create a simple project via IntelliJ

6. Expressions vs Statements
- Expression returns a value e.g. (1+3)
- Statement carries out an action e.g. (if-else)
- In Scala, almost every construct have a
value.

7. Conditional Expressions
- if (x > 0) 1 else -1
- This is also equivalent to
- x > 0 ? 1 : -1 (Java, C++)
- Every expression has a type
- Type of expression is supertype of both branches
- Unit type
- if (x >0) 1 else ()
- Think of () as placeholder for “No useful value”
- Think of Unit as analog to void. However void is like empty wallet,
whereas unit is like wallet with a bill labelled “No dollars”
- If condition multiple lines

8. Type Hierarchy

9. Loops
- while
- for

10. Pattern Matching
- Simple Matching
- Matching on Type
- Matching on Sequence
- Matching on Tuples