Sean Parsons seanparsons

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Setting A Status Message

seanparsons / Errors.

Created August 1, 2013 10:23

[error] (myproject/compile:compile) scala.reflect.internal.FatalError: class Universe does not have a member Quasiquote

seanparsons / EmbeddedHTMLImages.scala

Created July 31, 2013 22:38

	import org.apache.commons.codec.binary.Base64
	import java.nio.file._
	import java.nio.file.attribute._
	import scala.collection.mutable.ListBuffer

	val htmlTemplate = """
	<html>
	<head>
	<title>Encoded Images!</title>
	</head>

seanparsons / KleisliEnhance.scala

Created July 31, 2013 16:35

Automatic tuple conversion powered by macros.

	package myproject.util

	import myproject.macros._
	import scalaz._,Scalaz._,Kleisli._

	object KleisliEnhance {
	implicit class KleisliEnhancer[M[+_]: Monad, A, B](kleisli: Kleisli[M, A, B]) {
	def localFrom[AA]: Kleisli[M, AA, B] = kleisli.local(TupleTransformer.tupleToFrom[A, AA]
	}
	}

seanparsons / gist:6111532

Last active December 20, 2015 09:58

	def doThing[M[+_]: Monad, T, U, V]
	(actionOne: () => ReaderT[M, T, Unit],
	actionTwo: () => ReaderT[M, T, Unit],
	actionThree: () => ReaderT[M, T, Unit],
	actionFour: () => ReaderT[M, (T, U), Unit],
	actionFive: () => ReaderT[M, T, Unit,
	actionSix: () => ReaderT[M, V, Unit])
	(): ReaderT[M, (T, U, V), Unit] = {
	val tFromTriple: ((T, U, V)) => T = _._1
	val tuFromTriple: ((T, U, V)) => (T, U) = tup => (tup._1, tup._2)

seanparsons / gist:6010066

Created July 16, 2013 16:01

Idea for logging entry into methods.

	def logEntry() = macro logEntryImpl

	def method(param1: String, param2: Int): String = {
	logEntry()
	param1 * param2
	}

	// I'd want
	// logEntry()
	// to be replaced with

seanparsons / gist:5941234

Created July 6, 2013 20:48

Possible route to make for comprehensions stricter and powered by scalaz.Monad.

	def strictFor[M[+_], T](forExp: M[T])(implicit mMonad: Monad[M]): M[T] = macro strictForImpl[M, T]

	def strictForImpl[M[+_]: c.WeakTypeTag, T: c.WeakTypeTag](c: Context)(forExp: c.Expr[M[T]])(mMonad: c.Expr[Monad[M]]): c.Expr[M[T]] = {

seanparsons / LoopComparison.scala

Created April 12, 2013 22:09

Loops? No Thanks!

	// This bit is mostly getting imports together and some simple types.
	import scala.annotation.tailrec
	import scala.collection.mutable.ListBuffer
	import scalaz._,Scalaz._
	case class User(id: Int, name: String, score: Long)


	// EXAMPLE: Turn collection into another collection.

	// With a for loop (in this case a foreach):

seanparsons / gist:5361916

Last active December 16, 2015 02:19

Experimenting with sequenceU

	scala> import scalaz._,Scalaz._,effect._
	import scalaz._
	import Scalaz._
	import effect._

	scala> val list = List(IO(1).liftM[OptionT])
	list: List[scalaz.OptionT[scalaz.effect.IO,Int]] = List(OptionT(scalaz.effect.IOFunctions$$anon$5@52f3b59))

	scala> list.sequenceU
	res4: G.M[List[G.A]] = OptionT(scalaz.effect.IOFunctions$$anon$5@3beab0fc)

seanparsons / gist:5229917

Last active December 15, 2015 08:19

Quick attempt at timeout support for Scalaz Futures.

	import scalaz._
	import Scalaz._
	import scalaz.concurrent._
	import scala.annotation.tailrec
	import java.util.concurrent.locks.ReentrantReadWriteLock

	trait Timeout
	object Timeout extends Timeout

	case class Timer(timeoutTickMs: Int = 100, workerName: String = "TimeoutContextWorker") {

seanparsons / gist:5150889

Last active December 14, 2015 21:28

Experimenting with Scalaz Futures.

	scala> import scalaz._,Scalaz._,scalaz.concurrent._
	import scalaz._
	import Scalaz._
	import scalaz.concurrent._

	scala> (1 to 10).map(n => Future.fork(Future.delay{Thread.sleep(1000); n})).toList.sequence.run // Takes 10 seconds.
	res0: List[Int] = List(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)

	scala> Nondeterminism[Future].gather((1 to 10).map(n => Future.fork(Future.delay{Thread.sleep(1000); n})).toList).run // Takes 2 seconds.
	res1: List[Int] = List(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)