P. Oscar Boykin johnynek
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| def toBytesWritable(p: Pipe, f: Fields): Pipe = { | |
| import Dsl._ // Make sure we have the scalding DSL in scope: | |
| import Fields | |
| asList(f).foldLeft(p) { (oldPipe, fld) => | |
| oldPipe.map(fld -> fld) { str: String => new ImmutableBytesWritable(str.getBytes) } | |
| } | |
| } | |
| // Now call: |
johnynek
/ Example config
Created
April 4, 2013 01:11
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| supervisor1 { | |
| akka { | |
| actor { | |
| provider = "akka.remote.RemoteActorRefProvider" | |
| } | |
| remote { | |
| enabled-transports = ["akka.remote.netty.tcp"] | |
| netty.tcp { | |
| hostname = "0.0.0.0" | |
| port = 2554 |
johnynek
/ twitter_open_source.dot
Last active
December 17, 2015 10:19
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| // Run with | |
| // unflatten -l 7 ritchieboykin.gv | dot -Tpng -o ritchieboykin.png && open ritchieboykin.png | |
| digraph RitchieBoykin { | |
| page = "8.2677165,11.692913"; | |
| overlap=false; | |
| ratio = "auto"; | |
| mincross = 2.0; | |
| graph [style="filled, rounded", color=lightgrey, fillcolor=khaki, fontsize=10]; | |
| subgraph cluster_0 { |
johnynek
/ heterfn.scala
Created
June 18, 2013 04:29
An example showing how to make a function that takes one of many input types.
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| // Taken from: http://jnordenberg.blogspot.com/2008/08/hlist-in-scala.html | |
| object HListTest { | |
| sealed trait HList | |
| final class HNil extends HList { | |
| def ::[T](v : T) = HCons(v, this) | |
| } | |
| val HNil = new HNil() |
johnynek
/ LoggingMonad.scala
Last active
December 18, 2015 22:28
An example of a Monadic wrapper on Log4j
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| import org.apache.log4j.Logger | |
| sealed trait LogLevel | |
| case object Info extends LogLevel | |
| case object Warn extends LogLevel | |
| case object Error extends LogLevel | |
| sealed trait Logged[T] { | |
| def map[U](fn: T => U): Logged[U] |
johnynek
/ async_stream.scala
Last active
December 18, 2015 23:09
A simple API using Future and Promise to create an async stream.
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| // could easily be ported to Scala Future | |
| import com.twitter.util.{Promise, Future} | |
| trait Source[+T] { self => | |
| def head: Option[T] | |
| def tail: Future[Source[T]] | |
| def map[U](fn: T => U): Source[U] = new Source[U] { | |
| def head = self.head.map(fn) | |
| def tail = self.tail.map { _.map(fn) } | |
| } |
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| [info] Loading project definition from /Users/oscarb/workspace/chill/project | |
| [info] Compiling 1 Scala source to /Users/oscarb/workspace/chill/project/target/scala-2.9.2/sbt-0.12/classes... | |
| [info] Set current project to chill-all (in build file:/Users/oscarb/workspace/chill/) | |
| [info] Updating {file:/Users/oscarb/workspace/chill/}chill-all... | |
| [info] Updating {file:/Users/oscarb/workspace/chill/}chill-java... | |
| [info] Resolving org.scala-tools.testing#specs_2.9.3;1.6.9 ... | |
| [info] downloading http://oss.sonatype.org/content/repositories/releases/org/scalacheck/scalacheck_2.9.3/1.10.0/scalacheck_2.9.3-1.10.0-sources.jar ... | |
| [info] [SUCCESSFUL ] org.scalacheck#scalacheck_2.9.3;1.10.0!scalacheck_2.9.3.jar(src) (1248ms) | |
| [info] downloading http://oss.sonatype.org/content/repositories/releases/org/scala-tools/testing/specs_2.9.3/1.6.9/specs_2.9.3-1.6.9-sources.jar ... | |
| [info] [SUCCESSFUL ] org.scala-tools.testing#specs_2.9.3;1.6.9!specs_2.9.3.jar(src) (1838ms) |
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| class WriteOnce[T] { | |
| private val ref = new java.util.concurrent.atomic.AtomicReference[Option[T]](None) | |
| def init(t: T) { if(!ref.compareAndSet(None, Some(t))) sys.error("Already written"); } | |
| def get: Option[T] = ref.get | |
| } | |
| scala> val w = new WriteOnce[Int] | |
| w: WriteOnce[Int] = WriteOnce@215d55cb | |
| scala> w.get |
johnynek
/ compression.scala
Created
August 12, 2013 05:40
Compress Lists of any item (as long as they are immutable and have sane equals and hashCode). This is basically the Lempel-Ziv algorithm
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| /** | |
| scala> compress(List.fill(1000)(1)) | |
| res17: List[Either[Int,Int]] = List(Left(1), Right(0), Left(1), Right(1), Left(1), Right(2), Left(1), Right(3), Left(1), Right(4), Left(1), Right(5), Left(1), Right(6), Left(1), Right(7), Left(1), Right(8), Left(1), Right(9), Left(1), Right(10), Left(1), Right(11), Left(1), Right(12), Left(1), Right(13), Left(1), Right(14), Left(1), Right(15), Left(1), Right(16), Left(1), Right(17), Left(1), Right(18), Left(1), Right(19), Left(1), Right(20), Left(1), Right(21), Left(1), Right(22), Left(1), Right(23), Left(1), Right(24), Left(1), Right(25), Left(1), Right(26), Left(1), Right(27), Left(1), Right(28), Left(1), Right(29), Left(1), Right(30), Left(1), Right(31), Left(1), Right(32), Left(1), Right(33), Left(1), Right(34), Left(1), Right(35), Left(1), Right(36), Left(1), Right(37), Left(1), Ri... | |
| scala> compress(List.fill(1000)(1)).size | |
| res18: Int = 88 | |
| scala> decompress(res17) | |
| res19: List[Int] = List(1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, |
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| scala> class PostFix[A](a: A) { | |
| | def |>[B](fn: A => B): B = fn(a) | |
| | } | |
| defined class PostFix | |
| scala> implicit def toPf[A](a: A) = new PostFix(a) | |
| toPf: [A](a: A)PostFix[A] | |
| scala> val inc = { x: Int => x + 42 } | |
| inc: Int => Int = <function1> |