Kotlin compiler plugin that allows class delegation to be dynamic like property delegations.

The plugin is working in progress.

What does this plugin do

It provides a function

public fun <R> dynamicDelegation(value: () -> R): R =
    throw NotImplementedError("Implemented as intrinsic")

This function is implemented by the compiler. You can call this function on class delegation as follows:

interface TestClass {
    fun getResult(): Int
object TestObject : TestClass by (dynamicDelegation { getInstanceFromOtherPlaces() })

var called = 0
fun getInstanceFromOtherPlaces(): TestClass {
    val v = called++
    return object : TestClass {
        override fun getResult(): Int = v // static value here!

class Test {
    fun test() {
        assertEquals(0, TestObject.getResult())
        assertEquals(1, TestObject.getResult())
        assertEquals(2, TestObject.getResult())

Everytime fun getResult(): Int in TestObject is called, it calls the lambda { getInstanceFromOtherPlaces() } to
get a TestClass instance.

This eliminates your work against delegating the class manually.


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