>>> import kotlin.reflect.KProperty;
>>> class Delegate {
...    var inner = 1
...    operator fun getValue(t: Any?, p: KProperty<*>): Int = inner
...    operator fun setValue(t: Any?, p: KProperty<*>, i: Int) {
...        inner = i
...    }
...}

>>> var prop1: Int = 1
>>> prop1
1
>>> prop1 = 2
>>> prop1
2
>>> var prop2: Int = 100
>>> prop2
100
>>> prop2 = prop2 + 2
>>> prop2
102
>>> prop1
2