aryairani

object Factorial {
  implicit class LongFactorialPimp(x: Long) {
    require(x >= 0)
    def ! : Long = {
      if (x < 2) 1
      else x * ((x-1)!) // ! has the wrong precedence compared to * :(
    }
  }
  println(11!)
}

aryairani

// scalaVersion := "2.10.0-RC5"

// libraryDependencies += "org.scalaz" %% "scalaz-core" % "7.0.0-M6" cross CrossVersion.full
import scalaz.{OptionT,Writer} 
type Issue = String
type ListWriter[+A] = Writer[List[Issue],A]
type Box[+A] = OptionT[ListWriter,A]

object EmptyBox {
  def unapply[A](b: Box[A]): Option[List[Issue]] =

aryairani

trait SuperC[A,B] {
  def getB(a: A): B
  // ...
}

trait Foo {
  type A
  type B
  type C <: SuperC[A,B]
  // ...

aryairani

  trait AbstractAgent[S,A] {
    type Self = AbstractAgent[S,A]
    def learn(s: S): Self
  }

  trait GameDomain {
    type State
    type Action
    type Agent <: AbstractAgent[State, Action]
  }

aryairani

// Foo can be extended, and `step` should return the extended type
trait Foo[S,A] {
  type Self = Foo[S,A]
  def step(s: S): Self
}

// Bar can be extended, fixing a more specific F
trait Bar {
  type S
  type A

aryairani

implicit class Provided[A](f: A => A) {
  def provided(c: A => Boolean): A => A = 
    a => if (c(a)) f(a) else a
  
  def ->:(c: A => Boolean) = provided(c)
  def <--(c: A => Boolean) = provided(c)
}

def add(x: Int) = (_:Int) + x
val f1 = add(3) <-- (_ < 5)

aryairani

[alias]
        lol = log --graph --decorate --pretty=oneline --abbrev-commit
        lola = log --graph --decorate --pretty=oneline --abbrev-commit --all

aryairani

class Original<K,V> {
  public V get(final K key)
  {
    Session s;
    try {
        s = oGrid.getSession();
        ObjectMap map = s.getMap(cacheName);
        return (V) map.get(key);
    }
    catch (ObjectGridException oge)

aryairani

  implicit class RichProperties(properties: Properties) {
    import scalaz.syntax.std.boolean._

    def getIfTrue[T](key: String, value: => T) =
      (properties.get(key) == "true").option(value)
  }

aryairani

  val l = List("a","b","c","d")
  val getStyle = (k: Int) => l(k % l.length)
  val styles = List.tabulate(10)(getStyle)
  // styles: List[String] = List(a, b, c, d, a, b, c, d, a, b)

// or

  def getStyle[A](styles: Seq[A]) = (k: Int) => styles(k % styles.length)
  val l2 = List(1, 5, 9)
  val styles = List.tabulate(10)(getStyle(l2))