Chandler

abstract class PrintSomething() {
  def apply(s: String): Unit
}

object PrintSomething {

  /**
   * @param printMethod a method that prints something
   * @return a PrintSomething with an apply method
   * equal to your printMethod

Chandler

type PrintSomething = (String) => String

val printer1: PrintSomething = (s: String) => {
  print("\nI love " + s)
  s
}

val printer2: PrintSomething = (s: String) => {
  print("\nI hate " + s)
  s

Chandler

update, I have a test case here: https://gist.github.com/Chandler/7766963

I'm running it with multiple files as the input and cascading.hadoop.hfs.combine.files=true

When I run it against stock elephant bird it fails with the original error
"com.twitter.elephantbird.mapred.input.DeprecatedLzoTextInputFormat cannot be cast to org.apache.hadoop.mapred.FileInputFormat"

https://github.com/kevinweil/elephant-bird/pull/359
When I run it with Dmitriy's elephant bird patch it fails with "DeprecatedInputFormatWrapper can not support RecordReaders that don't return same key & value objects. current reader class : class com.twitter.elephantbird.mapreduce.input.LzoLineRecordReader"

Chandler

class myException extends Exception

object myObj {
 val ex = myException
}

// <console>:11: error: not found: value myException
//         val ex = myException

Chandler

//this works
def checkUnauthorizedException[T](t: Try[T]): TestResult =
  t match {
    case Throw(e) if e.isInstanceOf[UnauthorizedException] => TestResult.Success
    case  _ => TestResult.fail("found " + t.toString() + " but expected Throw[UnauthorizedException]")
  }


//possible to make this more generic? e.g. something like..

Chandler

case class MyException(errorCode: Int) extends RuntimeException

def onThrow[T <: Throwable](check: Check[T])(implicit m: Manifest[T]): Check[Try[_]] =  
  expected("A Throw(e: %s)".format(m.erasure)).exceptWhen { case Throw(NonFatal(e: T)) => check(e) }
  
val check = onThrow { 
  hasType[Unauthorized.type].on { e: ClientError => e.errorCause }
}

check(Throw(MyException(5)))

Chandler

   def myMethod { 
     val a: Option[Int] = someOption()
     if (a.isNone){
      //do a side effect (like increment a hadoop counter)
     }
     return a
   }

Chandler

def sideEffect() {
  //increment hadoop counter
}

val list = List(Some("a"),Some("b"),None, Some("e"), None)

val filtered = list.flatMap { x =>
  if(x.isEmpty) sideEffect()
  x
}

Chandler

 
case class WriteEvent(name: String, records: List[Int])

case class SingleRecord(name: String, value: Int)

val events = List( 
  WriteEvent("follow", List(1,2,3)),
  WriteEvent("block",  List(2,3,4)),
  WriteEvent("follow", List(5,6,7))
)

Chandler

scala>  def test(name: String = "joe"): Boolean = true
test: (name: String)Boolean

scala>  val test: String => Boolean = { (name: String = "joe") => true }
<console>:1: error: ')' expected but '=' found.