drstevens’s gists

drstevens / FutureUtil.scala

Created January 15, 2014 18:35 — forked from jlupien/FutureUtil.scala

	// Doesn't compile. Good.
	def futureInt(): Future[Int] = Future.value(Future.value(1))

	// Compiles. Not good. Caller cannot wait on completion of nested future.
	def futureUnit(): Future[Unit] = Future.value(Future.value(()))

	// Also compiles. Nice convenience, but not worth the cost of the issues
	// it might cause (as above), right?
	def futureUnit(): Future[Unit] = Future.value(1)

drstevens / IDEA run configuration

Last active December 31, 2015 21:39 — forked from mslinn/IDEA run configuration

-Dconfig.resource=test.conf -Dlogger.file=test/resources/logback-test.xml

drstevens / Foo.scala

Created December 16, 2013 21:32

Experiments with scalaz-stream. Attempt to maintain state by calls to next.

	import scala.collection.immutable
	import scalaz.std.string._
	import scalaz.std.list._
	import scalaz.std.anyVal._
	import scalaz.std.option._
	import scalaz.syntax.show._
	import scalaz.concurrent.Task
	import scalaz.stream.{process1, io, Process}
	import scalaz.stream.Process._

drstevens / gist:5579549

Last active December 17, 2015 08:19

Attempt to sequence List[StateT[Trampoline,A,B]]] with Trampoline in Scalaz 7. Unable to get this to work in scala 2.9.2 REPL. Works in 2.10.1 REPL. See https://gist.github.com/larsrh/5579789 also

	import scalaz.std.anyVal._
	import scalaz.std.tuple._
	import scalaz.std.option._
	import scalaz.StateT
	import scalaz.State
	import scalaz.Free
	import scalaz.Free._
	import scalaz.State._
	import scalaz.Trampoline._
	import scalaz.syntax.traverse._

drstevens / OptionMap.scala

Last active December 15, 2015 19:49

This example demonstrates benefits of using fold/cata instead of map and getOrElse on Option[T]. There are, of course, occasions when pattern matching is preferable as well.

	Welcome to Scala version 2.10.1 (Java HotSpot(TM) 64-Bit Server VM, Java 1.7.0_15).
	Type in expressions to have them evaluated.
	Type :help for more information.

	scala> val opt: Option[Int] = Some(10)
	opt: Option[Int] = Some(10)

	scala> val typeCheckFail = opt map (_ + "2") getOrElse (3)
	typeCheckFail: Any = 102

drstevens / Futures.scala

Created January 21, 2013 21:28

Define Apply[Future] in order to sequence. Written for Akka 1.3.1 (old, I know) and Scalaz 6.0.4. I imagine similar could be written for Akka 2.1.x and Scalaz 7. I've used this in many places so far without issue, but I've only used it for sequencing through something like `Validation[S, Future[Validation[S, Future[B]]]`. If I'm breaking some la…

	object FuturePimps {

	/**
	* Use this instead of new AlreadyCompletedFuture[T] to prevent accidental use of default Akka timeout
	**/
	def alreadyCompletedFuture[T](v: T)(implicit timeout: Timeout): AlreadyCompletedFuture[T] =
	new AlreadyCompletedFuture[T](Right(v), timeout.duration.toMillis)

	class FutureFuture[T](f: () => Future[Future[T]]) {
	def flatten: Future[T] = f().flatMap(identity)

drstevens / gist:4438371

Last active December 10, 2015 13:08 — forked from OleTraveler/gist:4347051

This demonstrates some of the ways to combine scalaz6 Validaitons. It is the result of answers to question http://stackoverflow.com/questions/13961940/chaining-scalaz-validation-functions-function1a-validatione-b. See answers for more, including combining functions using Kliesi in scalaz6 and scalaz7.



	def allDigits: (String) => ValidationNEL[String, String]
	def maxSizeOfTen: (String) => ValidationNEL[String, String]
	def toInt: (String) => ValidationNEL[String, Int]

	val validInt: String => ValidationNEL[String, Int] = s =>
	for {
	validStr <- (allDigits(s) \|@\| maxSizeOfTen(s))((_,x) => x)
	i <- toInt(validStr)

drstevens / TestHelpersSuite.scala

Created November 27, 2012 06:01

Provide more type safe equalizer implementation and provide a way to disable the implicit === conversion

	package com.bifflabs

	import org.scalatest.FunSuite
	import scalaz._
	import scalaz.Scalaz._

	class TestHelpersSuiteWithScalazSupport extends FunSuite with IgnoringDefaultEqualizer {
	import AssertionsWithScalazSupport._

	test("1 should equal 1") {

drstevens / Default (OSX).sublime-keymap

Created November 5, 2012 20:15

Fixing Home/End behavior in sublime. Add the following to the top of default of user keybindings 'Sublime Text 2' -> Preferences -> Keybindings

	/*
	On OS X, basic text manipulations (left, right, command+left, etc) make use of the system key bindings,
	and don't need to be repeated here. Anything listed here will take precedence, however.
	*/
	[
	{ "keys": ["home"], "command": "move_to", "args": {"to": "bol"} },
	{ "keys": ["end"], "command": "move_to", "args": {"to": "eol"} },
	{ "keys": ["shift+end"], "command": "move_to", "args": {"to": "eol", "extend": true} },
	{ "keys": ["shift+home"], "command": "move_to", "args": {"to": "bol", "extend": true } },
	...

drstevens / Validationz.scala

Created April 19, 2012 20:42

Convert List[Validation[A, B]] to Validation[List[A], List[B]]

	package com.mypackage

	import org.specs.SpecificationWithJUnit
	import scalaz._
	import Scalaz._

	class ValidationTests extends SpecificationWithJUnit {

	"I should be able to convert List[Validation[A, B]] to Validation[List[A], List[B]]" >> {