"find", "each" method throw type mismatch error

Question

I am trying to iterate over options using val x = $(selectState).find("option").each((y: Element) => y). However Compilation throw following error.

type mismatch;
 found   : org.scalajs.dom.Element => org.scalajs.dom.Element
    (which expands to)  org.scalajs.dom.raw.Element => org.scalajs.dom.raw.Element
 required: scala.scalajs.js.|[scala.scalajs.js.ThisFunction0[org.scalajs.dom.Element,Any],scala.scalajs.js.ThisFunction1[org.scalajs.dom.Element,Int,Any]]
    (which expands to)  scala.scalajs.js.|[scala.scalajs.js.ThisFunction0[org.scalajs.dom.raw.Element,Any],scala.scalajs.js.ThisFunction1[org.scalajs.dom.raw.Element,Int,Any]]

I was referring to stack overflow question here.

Based on the issue you raised in jquery-facade, I assume you're using that. It's odd -- I don't see offhand why that call to `each` isn't compiling. I'll try to look into that today, and see if I can figure out what's up. (Might be that the use of `|` is preventing the Scala function from implicitly converting to a JavaScript one, in which case I'll need to rewrite the facade for `each`.) — Justin du Coeur, Apr 06 '16 at 12:04
Working on it now -- I've repro'ed the problem, and am confirming the cause... — Justin du Coeur, Apr 06 '16 at 12:26

score 0 · Accepted Answer · answered Apr 06 '16 at 13:00

Okay, answering this formally: yep, that was a bug in jquery-facade. Thanks for pointing it out!

The issue, as I suspected, was that the | type operator interferes with the compiler's ability to automatically cast Scala functions to JavaScript ones. So it wasn't understanding that (y: Element) => y (a Scala function) could be turned into a JavaScript js.Function0[Element, Any].

So I've split each into two separate overloads, one for each version, and that appears to work as desired. Please update to jquery-facade 1.0-RC3, and I think it should work for you.

"find", "each" method throw type mismatch error

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