FILE: main.kt
    public? final? fun Y.test(): String? {
        lval a: <implicit> = when (this#) {
            ($subj$ is F) ->  {
                IntegerLiteral(1)
            }
            ($subj$ is G) ->  {
                IntegerLiteral(2)
            }
            else ->  {
                ^test Null(null)
            }
        }

        ^test Null(null)
    }
