Jamie Thompson bishabosha

Language design ❤️

bishabosha / summon-semigroup-maybe-oldway.scala

Created November 15, 2021 16:00

demonstration that the cats style of type class definition and syntax does not play well with type inference

	// using scala 3.1.0

	package mycats:

	trait Semigroup[A]:
	def combine(a1: A, a2: A): A

	class SemigroupOps[A](a1: A)(implicit ev: Semigroup[A]):
	def combine(a2: A): A = ev.combine(a1, a2)

bishabosha / summon-semigroup-Maybe.scala

Created November 15, 2021 15:20

Summon a Semigroup for Maybe, defined as an enum

	// using scala 3.1.0
	// using lib org.typelevel::cats-core:2.6.1

	package good

	import cats.Semigroup
	import cats.syntax.all.*

	enum Maybe[+A]:
	case Just(a: A)

bishabosha / OpaqueTypeEntities.worksheet.sc

Created March 10, 2021 14:40

Demonstrate using Opaque Type Aliases as evidence parameters to abstract over different storage

	object Notarisation:

	private case object Proven

	opaque type Proof <: Singleton = Proven.type
	given Proof = Proven

	end Notarisation

	import Notarisation.Proof

bishabosha / migrating-package-objects-with-extends.md

Created January 23, 2020 13:40

Migrating package objects with extends clauses

Here is a trait in package p

package p
trait Aliases { type Env = A with B }

In Scala 2, you could do this:

package object p extends Aliases

bishabosha / prettyPrint.scala

Last active April 16, 2019 23:49

Dotty tail recursive object pretty print - naive indentation