| // details: https://stackoverflow.com/questions/44159203/shapeless-checking-of-the-type-constraints-of-polymorphic-functions-lifted-ty | |
| import shapeless._ | |
| import ops.hlist._ | |
| import ops.function._ | |
| import syntax.std.function._ | |
| object ShapelessExample { | |
| case class Place[A](a: A) extends AnyVal |
| package test | |
| import scala.collection.mutable | |
| import scala.reflect.ClassTag | |
| /** | |
| * A Source of elements of type [[A]]. | |
| * | |
| * [[Source]] is basically the inverse of | |
| * a `scala.Iterator`: instead of the core functionality being the pull-based |
#Haskell, Stack and Intellij IDEA IDE setup tutorial how to get started Upon completion you will have a sane, productive Haskell environment adhering to best practices.
Don't install Haskell, Stack, Cabal or any other Haskell tool or library using your OS package manager or using Cabal.
Links on Must watch talks
A Year living Freely - Chris Myers
Programs as Values Pure Composable Database Access in Scala. In general each talk from Rob Norris is very useful for learning.
| #!/usr/bin/env amm | |
| load.ivy("org.typelevel" %% "cats" % "0.7.0") | |
| @ | |
| import cats.{Id, ~>} | |
| import cats.data.State | |
| import cats.free._ | |
| import cats.free.Free._ |
Copyright © 2017 Fantasyland Institute of Learning. All rights reserved.
A function is a mapping from one set, called a domain, to another set, called the codomain. A function associates every element in the domain with exactly one element in the codomain. In Scala, both domain and codomain are types.
val square : Int => Int = x => x * x
| import scalaz._ | |
| import Scalaz._ | |
| import Free._ | |
| /** "Pure" interactions with a console. */ | |
| sealed trait Console[+A] | |
| case class GetLine[A](k: String => A) extends Console[A] | |
| case class PutLine[A](s: String, a: A) extends Console[A] | |
| object Console { |
| import scalaz.effect.IO | |
| import scalaz.std.function._ | |
| import scalaz.{Coyoneda, Free, Monad, State, ~>} | |
| object NonFunctor extends App { | |
| // my simple algebra | |
| sealed trait Console[A] | |
| case class PrintLine(msg: String) extends Console[Unit] | |
| case object ReadLine extends Console[String] |
| trait State[S, A] { | |
| val run: S => (S, A) | |
| def apply(s: S): (S, A) = | |
| run(s) | |
| def eval(s: S): A = | |
| apply(s)._2 |
| val drone = new ARDrone("192.168.1.1") | |
| dron.connect(); | |
| if(drone.hasVideo) { | |
| // | |
| val bufferedImage = drone.video().getFrame() |