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`js.UndefOr` is no longer considered a subtype of `js.Any`

See original GitHub issue

Compiler version

2.13.5 - pass
3.0.0-RC1 - pass
3.0.0-RC2 - fail
3.0.0-RC3 - fail

Minimized code

import scala.scalajs.js

object Test {
  def x: js.UndefOr[Int] = 1
  x: js.Any
}

Output

[error] 5 |  x: js.Any
[error]   |  ^
[error]   |  Found:    scala.scalajs.js.UndefOr[Int]
[error]   |  Required: scalajs.js.Any
[error] one error found

Expectation

Success.

Issue Analytics

State:
Created 2 years ago
Comments:10 (10 by maintainers)

Top GitHub Comments

1reaction

smartercommented, Apr 28, 2021

if we just wanted to support conversions from js.UndefOr and not all unions of primitives, we could add an implicit def to https://github.com/lampepfl/dotty/blob/master/library-js/src/scala/scalajs/js/internal/UnitOps.scala in 3.1.

0reactions

japgollycommented, Apr 28, 2021

Oh silly me, 99% of the time we import scala.scalajs.js, not import scala.scalajs.js._ which is different to expected usage with most of my own libraries. Ok yep my bad, you’re right.

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