JSMacro should support union types

[mariussoutier]

When using union types, one must cast to js.Any, e.g.:

case class Pie(padding: js.UndefOr[Double | Shape] = js.undefined) {
  def toJs = {
    val p = js.Dynamic.literal()
    padding.foreach(x => p.updateDynamic("padding")(x.asInstanceOf[js.Any]))
    p
  }
}

JSMacro doesn't know about this, so this compiler error comes up:

type mismatch;
 found   : scala.scalajs.js.|[Double,Shape]
 required: scala.scalajs.js.Any

[chandu0101]

hey you need this import

import chandu0101.scalajs.react.components._

https://github.com/chandu0101/scalajs-react-components/blob/master/core/src/main/scala/chandu0101/scalajs/react/components/package.scala#L16

[mariussoutier]

Ah thanks.

The import is package private, so I can't use it for my own stuff. I copied the code, but it produces strange errors in Play that it can't find its config files...

[oyvindberg]

I'm not sure what to do about this. The implicit that we use is not safe in the general case, which is why we no longer export it (see scala-js/scala-js#2070 for details), but you can easily provide your own. Or cast yourself, like you figured out.

Would @sjrd have any idea, perhaps?

[mariussoutier]

What do you mean, it's not safe?

[oyvindberg]

safe as in, you can get runtime exceptions

[mariussoutier]

Thanks. Then I'll use my internal version for now.