Kotlin null check for multiple nullable var's

Language Design
48

I solved this by creating some functions that more or less replicates the behavior of with, but takes multiple parameters and only invokes the function of all the parameters is non-null.

fun <R, A, B> withNoNulls(p1: A?, p2: B?, function: (p1: A, p2: B) -> R): R? = p1?.let { p2?.let { function.invoke(p1, p2) } }
fun <R, A, B, C> withNoNulls(p1: A?, p2: B?, p3: C?, function: (p1: A, p2: B, p3: C) -> R): R? = p1?.let { p2?.let { p3?.let { function.invoke(p1, p2, p3) } } }
fun <R, A, B, C, D> withNoNulls(p1: A?, p2: B?, p3: C?, p4: D?, function: (p1: A, p2: B, p3: C, p4: D) -> R): R? = p1?.let { p2?.let { p3?.let { p4?.let { function.invoke(p1, p2, p3, p4) } } } }
fun <R, A, B, C, D, E> withNoNulls(p1: A?, p2: B?, p3: C?, p4: D?, p5: E?, function: (p1: A, p2: B, p3: C, p4: D, p5: E) -> R): R? = p1?.let { p2?.let { p3?.let { p4?.let { p5?.let { function.invoke(p1, p2, p3, p4, p5) } } } } }

Then I use it like this:

withNoNulls("hello", "world", Throwable("error")) { p1, p2, p3 ->
    p3.printStackTrace()
    p1.plus(" ").plus(p2)
}?.let {
    Log.d("TAG", it)
} ?: throw Exception("One or more parameters was null")

The obvious issue with this is that I have to define a function for each case (number of variables) I need, but at least I think the code looks clean when using them.

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