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kotlinlang

<@U3QQ65FUZ> What kind of vars are those? Why are they nullable? Have you tried using `lateinit`? Can you share some code?

<@U2E974ELT> an example: my app has a list of place cards (for all the nearby hotels)…because they’re reusable views in a `PagerAdapter`, each `PlaceCardView` can be in a different state (loading, showing a place, or showing the “no nearby places” state).  `PlaceCardView` has a `private var place: Place? = null` property and three modifier methods (`showPlace(place: Place)`, `showLoading()`, `showNoNearbyPlaces()`) that set/unset the `place` var

then the click listeners for the various views all have to do
```
foo.setOnClickListener { 
  val place = place
  if (place == null) {
    // do a thing
  } else {
    // do the other thing
  }
}
```

lateinit doesn’t work because i need to check if the value is set or not and i need to be able to unset it.

the alternative is to call `setOnClickListener` every time the `place` changes, but that feels even more gross to me in this case

Use `EmptyObject` pattern. Make a singleton `object Nowhere : Place` and use it whenever place is not defined. You will save yourself a lot of issues with null handling.

i thought the whole point of modelling optional things in the type system was to take advantage of that nullability? :slightly_smiling_face:

Well, it’s not a silver bullet, sometimes other tools suite better