Juan José Vázquez juanjovazquez

Coder for fun and profit.

juanjovazquez / polyMatch.scala

Created May 26, 2020 08:47

Scala 3 poly functions on match types

	type Negate[X] = X match
	case String => String
	case Int => Int
	case Boolean => Boolean

	def negate[A](a: A): Negate[A] = a match
	case x: String => s"no-$x"
	case x: Int => -x
	case x: Boolean => !x

juanjovazquez / polyMap.scala

Created May 26, 2020 12:26

Errors using context bounded poly functions in Scala 3

	package polyMap

	type Id[T] = T

	trait Negation[A]:
	def neg(a: A): A

	object Negation:
	def apply[A](using ev: Negation[A]): Negation[A] = ev

juanjovazquez / Field0.scala

Created December 20, 2021 12:45

erasedValue seems not work with opaque types

	// Regular class
	final case class Field0[L <: String & Singleton, V](label: L, value: V)

juanjovazquez / Displays.scala

Created November 1, 2022 16:55

Emulating polymorphic functions on polymorphic collections

	package polycol

	object Displays {
	import PolyCol.*

	opaque type Display = String

	object Display {
	def apply[A: Printer](a: A): Display = a.print
	}