justinhj

// Tuples, integers and maps all have monoid 
// instances we can easily combine them

@ val data = "Hello Hello This is some data data data yo" 
data: String = "Hello Hello This is some data data data yo"

@ def step(word: String) = (1, word.length, Map(word -> 1)) 
defined function step

@ def run(data: String) = data.split(" ").toList.map(step).combineAll 

justinhj

package examples

import scalaz._, Scalaz._

object ContravariantMap {

// Example of contravariant using Scalaz
  trait Printable[A] {
    def format(value: A): String
  }

justinhj

import java.util.concurrent.TimeoutException
import java.util.{Timer, TimerTask}

import scala.concurrent.duration._
import scala.concurrent.{Await, ExecutionContext, Future, Promise}
import scala.language.postfixOps
import scala.util.{Failure, Success, Try}

object FutureUtil {

justinhj

import           Data.List

-- Graham Scan

-- Direction data type
data Direction = Left
  | Right
  | Straight
  deriving (Eq, Show)

justinhj

# http://www.lihaoyi.com/post/BuildyourownCommandLinewithANSIescapecodes.html

# Colours

print "\u001b[30m A \u001b[31m B \u001b[32m C \u001b[33m D \u001b[0m\n"
print "\u001b[34m E \u001b[35m F \u001b[36m G \u001b[37m H \u001b[0m\n"
print "\n"

# Bright colours

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/*
val CatsMTLVersion = "0.4.0"
val CatsVersion = "1.4.0"
val CatsEffectVersion = "1.0.0"

libraryDependencies ++= Seq(
  "org.typelevel" %% "cats-core" % CatsVersion,
  "org.typelevel" %% "cats-effect" % CatsEffectVersion,
  "org.typelevel" %% "cats-mtl-core" % CatsMTLVersion,
*/

justinhj

  // Functor
  trait JFunctor[F[_]] {

    def map[A,B](fa: F[A])(f: A => B) : F[B]

  } 

  trait JMapFunctor[K] extends JFunctor[({type LT[V] = Map[K, V]})#LT] {

    def map[A, B](fa: Map[K,A])(f: A => B): Map[K,B] = {

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module RomanConvert exposing (..)

import Dict exposing (Dict, fromList)
import List.Extra exposing (find)
import Set exposing (..)


-- Elm implementation of converting to and from Integer and a string representation of a Roman Numeral
-- (C)2018 Justin Heyes-Jones
-- These are the valid characters that make up Roman Numerals

justinhj

Scalaz
Symbol	Code	Ascii	Example
η	951	pure	1.η[List]
μ	03BC	join	List(List(1,2,3), nil, List(5,6,7)) μ
∅	2205	zero	∅[Int]
<∅>		empty	<∅>[Option, Int]
∙	2219	contramap	((_:String).length ∙ (_:Int).toString ∙ ((_:Int) + 6))(5)
∘	2218	map	(((_:Int) + 6) ∘ (_:Int).toString ∘ (_:String).length)(5)
∘∘

"map2":https://github.com/scalaz/scalaz/blob/master/core/src/main/scala/scalaz/MA.scala#L326

justinhj

package com.heyesjones.fs2redis

import cats.effect.{Effect, IO}
import com.redis._
import com.typesafe.scalalogging.LazyLogging
import fs2.{async, _}

import scala.concurrent.ExecutionContext
import scala.util.{Failure, Success, Try}