Scala
Hello world
object HelloWorld { def main(args: Array[String]) {
println("Hello world!") }}
public class HelloWorld { public static void main(String[] args)
{ System.out.println("Hello world"); }}
scala> var peaks = Map( | "Musala" -> 2925, | "Rozhen"
-> 1750 | )peaks:
scala.collection.immutable.Map[java.lang.String,Int] = Map(Musala
-> 2925, Rozhen -> 1750)
scala> peaks += "Botev" -> 2376
scala> println(peaks)Map(Musala -> 2925, Rozhen ->
1750, Botev -> 2376)
Java
public boolean hasUpperCase(String text) { boolean hasUpperCase
= false; for (int i = 0; i < text.length(); i++) { if
(Character.isUpperCase(text.charAt(i))) { hasUpperCase = true;
break; } } return hasUpperCase;}
Scala
def hasUpperCase(text: String) = text.exists(_.isUpperCase)
Java
public BigInteger ?????(BigInteger x) { if (x ==
BigInteger.ZERO) { return BigInteger.ONE; } return x.multiply(
?????(x.subtract(BigInteger.ONE)));}
Java
public BigInteger factorial(BigInteger x) { if (x ==
BigInteger.ZERO) { return BigInteger.ONE; } return x.multiply(
factorial(x.subtract(BigInteger.ONE)));}
def factorial(x: BigInt) = if (x == 0) 1 else x * factorial(x -
1)
Scala
Java
public class Person { private String name; private int age;
public Person(String name, int age) { this.name = name; this.age =
age; } public String getName() { return name; } public int getAge()
{ return age; } public void setName(String name) { this.name =
name; } public void setAge(int age) { this.age = age; }}
class Person(var name: String, var age: int)
Scala
Turtles all the way down
http://en.wikipedia.org/wiki/Turtles_all_the_way_down
1 + 21.+(2)
1 to 8 // => Range.Inclusive(1, 8)1.to(8)
def users = { user.name } { user.password } { user.email } {
boss.name } { boss.password } { boss.email }
users \ "user"
DSLs
Growing a language
http://video.google.com/videoplay?docid=-8860158196198824415
Scala specs
object HelloSpec extends Specification { "'hello world' has 11
characters" in { "hello world" size must_== 11 } "'hello world'
matches 'h.* w.*'" in { "hello world" must be matching("h.* w.*")
}}
object Basic extends Baysick { def main(args:Array[String]) = {
10 PRINT "Welcome to Baysick Lunar Lander v0.9" 20 LET ('dist :=
100) 30 LET ('v := 1) 40 LET ('fuel := 1000) 50 LET ('mass :=
1000)
60 PRINT "You are drifting towards the moon."
70 PRINT "You must decide how much fuel to burn." 80 PRINT "To
accelerate enter a positive number" 90 PRINT "To decelerate a
negative"
100 PRINT "Distance " % 'dist % "km, " % "Velocity " % 'v %
"km/s, " % "Fuel " % 'fuel 110 INPUT 'burn 120 IF ABS('burn)
