scalolli

doi=10.1097%2F00125817-200001000-00001&doi=10.1097%2F00125817-200001000-00002&doi=10.1097%2F00125817-200001000-00003&doi=10.1097%2F00125817-200001000-00004&doi=10.1097%2F00125817-200001000-00005&doi=10.1097%2F00125817-200001000-00006&doi=10.1097%2F00125817-200001000-00007&doi=10.1097%2F00125817-200001000-00008&doi=10.1097%2F00125817-200001000-00009&doi=10.1097%2F00125817-200001000-00010&doi=10.1097%2F00125817-200001000-00011&doi=10.1097%2F00125817-200001000-00012&doi=10.1097%2F00125817-200001000-00013&doi=10.1097%2F00125817-200001000-00014&doi=10.1097%2F00125817-200001000-00015&doi=10.1097%2F00125817-200001000-00016&doi=10.1097%2F00125817-200001000-00017&doi=10.1097%2F00125817-200001000-00018&doi=10.1097%2F00125817-200001000-00019&doi=10.1097%2F00125817-200001000-00020&doi=10.1097%2F00125817-200001000-00021&doi=10.1097%2F00125817-200001000-00022&doi=10.1097%2F00125817-200001000-00023&doi=10.1097%2F00125817-200001000-00024&doi=10.1097%2F00125817-200001000-00025&doi=10.1097%2F00125817-200001000-00026&doi=10.109

scalolli

sbt:contenthub-api> runtime:dependencyTree
[warn] There may be incompatibilities among your library dependencies; run 'evicted' to see detailed eviction warnings.
[warn] There may be incompatibilities among your library dependencies; run 'evicted' to see detailed eviction warnings.
[warn] There may be incompatibilities among your library dependencies; run 'evicted' to see detailed eviction warnings.
[info] contenthub:contenthub-api-ontologies_2.12:LOCAL
[info] com.getsentry.raven:raven-logback:8.0.3
[info]   +-ch.qos.logback:logback-classic:1.2.1 (evicted by: 1.2.3)
[info]   +-ch.qos.logback:logback-classic:1.2.3
[info]   | +-ch.qos.logback:logback-core:1.2.3
[info]   | +-org.slf4j:slf4j-api:1.7.25 (evicted by: 1.7.28)

scalolli

import cats.effect.IO
import io.circe.{Decoder, Json}
import org.http4s.circe._
import org.http4s.{Response, Status}
import org.scalatest.EitherValues
import org.scalatest.matchers.{HavePropertyMatchResult, HavePropertyMatcher}

trait Http4sMatchers { this: EitherValues =>
  def status(expected: Status) = HavePropertyMatcher { response: Response[IO] =>
    HavePropertyMatchResult(matches = response.status == expected,

scalolli

module MyList where

  import Data.Monoid
  import Test.QuickCheck
  import Test.QuickCheck.Classes
  import Test.QuickCheck.Checkers

  data List' a = Nil' | Cons' a (List' a) deriving (Eq, Show)

  instance Monoid (List' a) where

scalolli

λ> (\x -> Cons' x Nil') <$> (Just $ Right 5)
Just (Cons' (Right 5) Nil')

-- The whole reason of using Compose is acting as a type constructor, here we ended up making Just and Right part
-- of the Compose structure hence we only 5 is passed to the function (\x -> Cons' x Nil)
λ> (\x -> Cons' x Nil') <$> (Compose $ Just $ Right 5)
Compose (Just (Right (Cons' 5 Nil')))

scalolli

  import Data.Monoid

  data List' a = Nil' | Cons' a (List' a) deriving (Eq, Show)

  instance Monoid (List' a) where
    mempty = Nil'

    mappend x Nil'  = x
    mappend Nil' x = x
    mappend (Cons' a xs) ys = Cons' a $ xs <> ys

scalolli

sealed trait Or[A, B]
object Or {
case class FstA, B extends Or[A, B]
case class SndA, B extends Or[A, B]
}

implicit def eqOr[A: Eq, B: Eq]: Eq[Or[A, B]] = Eq.fromUniversalEquals
implicit def arbitraryOrA, B: Arbitrary[Gen[Or[A, B]]] = Arbitrary(
Gen.oneOf(Seq(Arbitrary.arbitrary[A].map(Fst()), Arbitrary.arbitrary[B].map(Snd())))
)

scalolli

import cats.implicits._

def parseInt(s: String): Either[NumberFormatException, Int] = Either.catchOnly[NumberFormatException](s.toInt)

List("1", "2", "3").traverse(parseInt)

scalolli

fmap (*2) (+1) $ 1
so that returns 4 

But why can I not do 
(fmap (*2) (+)) 1 2 ?

scalolli

-- Functor for Company a b c

  data Company a b c = DeepBlue a c | Something b deriving (Eq, Show)

  instance Functor (Company a b) where
    fmap f (DeepBlue a c) = DeepBlue a (f c)
    fmap f (Something b) = Something b

  instance (Arbitrary a, Arbitrary b, Arbitrary c) => Arbitrary (Company a b c) where
    arbitrary = do