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Use-site `nonsensical` error with "sequence match" variadic extractor

See original GitHub issue

Compiler version

3.2.1-RC2 / 3.2.0

Minimized code & Output

class Foo
type T1
type T2 <: T1
type T3 <: T1

object Foo1:
  def unapplySeq(f: Foo) = Foo2

object Foo2:
  def lengthCompare(len: Int): Int = ???
  def apply(i: Int): T1 = ???
  def drop(n: Int): scala.Seq[T2] = ???
  def toSeq: scala.Seq[T3] = ???

new Foo match
  case Foo1(x1,x2,x3) => println(s"$x1,$x2,$x3") // error:
// Recursive <nonsensical>value $t</nonsensical> needs type

https://scastie.scala-lang.org/fwuFJYs1RZOjgCK6Y3xzqA

Without the match no error is thrown

Expectation

This looks like it should be a valid instance of a “sequence match” (as seen here), so it should not throw any errors

Issue Analytics

State:
Created a year ago
Comments:5 (3 by maintainers)

Top GitHub Comments

1reaction

Sporarumcommented, Oct 3, 2022

It appears this bug was already posted as an issue on Scastie … by me … https://github.com/scalacenter/scastie/issues/635

0reactions

Sporarumcommented, Oct 3, 2022

It appears to be a wrapping bug, as even in Scastie, putting the expression in a def solves the issue: https://scastie.scala-lang.org/7KGmjykfQXOwVcj1X5GQqw

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