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kotlinlang

```
class A {
    val foo = "hello"
}
class B(a: A) {
    init {
        a.foo.bar // null pointer
    }
}
````

my `foo` isn't a string. It's just a method of the field

Could you post a snippet of the actual code so that we can see what might wrong?

E.g. also how the constructor of the `B` class is called.

hm yeah I can't reproduce it with this snippet. Will play a bit with a scratch and post if I can't figure it out

ok, so the problem is this
```
class B(a: A) {
    init {
        println(a.foo.length)
    }
}

class A {
    val b = B(this)
    val foo = "hello"
}

B(A())
```
And the solution is to move the line with `val foo = "hello"` above the one that's initializing `B`

yes, this makes sense. `foo` has not yet been initialized when you access it in `B`’s constructor block

Try something like this. It won’t run:
```
open class A(val b: B)
open class B(val a: A)

object objectA : A(objectB)
object objectB : B(objectA)
```

If you change it to this:
```
open class A(val b: B?)
open class B(val a: A?)
```
Then the value of `objectA.b` or `objectB.a` may or may not be null… :slightly_smiling_face:

yeah I understand the reason... bit hairy :smile:

you probably did this already, if not, just exchange the lines in A
```class B(a: A) {
    init {
        println(a.foo.length)
    }
}

class A {
    val foo = "hello"
    val b = B(this)
}

B(A())```