A modern programming language that makes developers happier.

kotlinlang

Here's an interesting one;
```interface Foo {
    fun foo()
}

enum class Bar : Foo by Companion {
    One,
    Two,
    ;

    companion object : Foo {
        override fun foo() {
            println("Bar.foo")
        }
    }
}

Bar.One.foo()```
```java.lang.NullPointerException: Cannot invoke "Scratch_18$Bar$Companion.foo()" because "this.$$delegate_0" is null
	at Scratch_18$Bar.foo(scratch_18.kts)
	at Scratch_18.<init>(scratch_18.kts:22)```
<https://youtrack.jetbrains.com/issue/KT-79692>

This one was surprisingly easy to pinpoint and miniaturize, which is rare