Hi all. In the following code channel variable in ...

# coroutines

[Stanislav Shamilov]

Hi all. In the following code channel variable in the statement this.channel.offer(it ?: “”) is highlighted with a warning “Non-applicable call for builder inference”.

fun EditText.textChanges(): Flow<String> = callbackFlow {
    val textWatcher = textWatcher(afterText = {
        this.channel.offer(it ?: "")
    })
    [e-mail](textWatcher)
    awaitClose { [e-mail]r(textWatcher) }
}

private fun textWatcher(
    beforeText: (String?) -> Unit = {},
    onText: (String?) -> Unit = {},
    afterText: (String?) -> Unit = {}
): TextWatcher {
    return object : TextWatcher {
        override fun afterTextChanged(s: Editable?) = afterText(s?.toString())
        override fun beforeTextChanged(s: CharSequence?, start: Int, count: Int, after: Int) = beforeText(s?.toString())
        override fun onTextChanged(s: CharSequence?, start: Int, before: Int, count: Int) = onText(s?.toString())
    }
}

Kotlin version: 1.3.50
Coroutines version: 1.3.0
IDE: Android Studio 3.5

I have two questions:
1. Why does this warning show up?
2. What does this warning stand for?

Thanks in advance!