This document provides an overview of the Scala programming language. It notes that Scala is a multi-paradigm language created in 2003 by Martin Odersky that runs on the JVM. It supports both object-oriented and functional programming. Some key features highlighted include functions being treated as values, pattern matching, case classes, and high order functions. Examples are provided of common functional operations like filtering, mapping and reducing collections as well as using anonymous functions.

1. Marcelo Cure

2. WTF is Scala?
 Multi-paradigm programming lang
 Created on 2003 by Martin Odersky
 Based on Java
 Compiled into Java Byte Code
 Runs under JVM
 Integration with Java

3. Functional Paradigm
 Executed evaluating expressions
 Avoids using mutable state
 Functions treated as values(can be
passed as functions)
 No side effects
 Expressiveness
 Less Bugs
 Simpler
 Less code

4. Difference example

5. List manipulation
scala> val list = (1 to 12).toList
list: List[Int] = List(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
scala> list.filter(_ % 2 == 0)
res1: List[Int] = List(2, 4, 6, 8, 10, 12)
scala> val list = (1 to 12).toList
list: List[Int] = List(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
scala> val list2 = list.map(_ * 2)
list2: List[Int] = List(2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24)
scala> list2.reduceLeft(_ + _)
res2: Int = 156

6. FlatMaps
scala> val fruits = Seq("apple", "banana", "orange")
fruits: Seq[String] = List(apple, banana, orange)
scala> fruits.flatMap(_.toUpperCase)
res13: Seq[Char] = List(A, P, P, L, E, B, A, N, A, N, A, O, R, A, N, G, E)

7. Anonymous Functions
scala> var sum = (x:Int,y:Int) => x + y
sum: (Int, Int) => Int = <function2>
scala> sum(1,2)
res3: Int = 3

8. Pattern Matching
scala> def toYesOrNo(choice: Int): String = choice match {
| case 1 => "yes"
| case 0 => "no"
| case _ => "error"
| }
toYesOrNo: (choice: Int)String
scala> println(toYesOrNo(1))
yes
scala> println(toYesOrNo(0))
no
scala> println(toYesOrNo(3))
error

9. Case Class
 Plain and immutable data-holding
objects
 Depends exclusively on its constructor
arguments.
scala> case class Node(left: Int, right: Int)
defined class Node
scala> var node1 = Node(1,2)
node1: Node = Node(1,2)

10. High Order Functions
 Takes other functions as parameter
 Return functions
scala> def apply(f: Int => String, v: Int) = f(v)
apply: (f: Int => String, v: Int)String
scala> def layout[A](x: A) = "[" + x.toString() + "]"
layout: [A](x: A)String
scala> println( apply( layout, 10) )
[10]

11. Web Frameworks
 Lift Framework
 Play framework
 Bowler framework

12. End