Just wondering why the following Kotlin code ```pr...

# javascript

[Edoardo Luppi]

Just wondering why the following Kotlin code

private fun replOrThrow(message: String): Char {
  val repl = this.replacement // = private var replacement: Char? = '\uFFFD'

  if (repl != null) {
    return repl
  }

  throw MessageCharacterCodingException(message)
}

is translated to:

function replOrThrow_1($this, message) {
  var repl = $this.qe_1;
  var tmp = repl;
  if (!((tmp == null ? null : new Char(tmp)) == null)) {
    return repl;
  }
  throw MessageCharacterCodingException.xd(message);
}

Specifically the new Char(tmp) thing. It looks like the char is not being treated as a simple number in this case (making it non-nullable doesn't help).

[Artem Kobzar]

It looks weird for me too. Could you please fill out an issue for it?

[Edoardo Luppi]

Will do, thanks!

[broadway_lamb]

This is because we treat Char as a value class. Values of such classes are always boxed when they are put into a nullable storage.

This makes sense on other targets like JVM, Native and Wasm, but on JS we indeed could do better.

[Edoardo Luppi]

Created https://youtrack.jetbrains.com/issue/KT-77570

[Edoardo Luppi]

Seems like the Char class is the only one for which you reserve a special treatment, at least by looking at the sources.
At least (I hope) the scope is limited.