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```?.takeIf { id -&gt; session.classFromId(id)?.isAnnotationClass() == true }```
Is there a version of `takeIf` that lets me return `Boolean?` or a better idiom to use here to obviate the `== true`?

`== true` is the idiom here.
Dealing with `Boolean?` Is hard. There's no simple rule as to what `null` should map to. Sometimes you genuinely want to use `== false`.
If the expression gets big enough, early returns can be very helpful:
```?.takeIf { id -&gt;
  val klass = session.classFromId(id) ?: return@takeIf false
  klass.isAnnotationClass()
}```

Why not
```?.takeIf { id -> 
  session.classFromId(id)?.isAnnotationClass() ?: false 
}```
or (depending on your logic)
```?.takeIf { id -> 
  session.classFromId(id)?.isAnnotationClass() 
} ?: false ```

That works as well, and is equivalent
I vaguely remember the `==` pattern being considered more idiomatic for some reason, but hey it's all personal preference at the end of the day

This kind of question is what AI is used for

<https://kotlinlang.org/docs/coding-conventions.html#nullable-boolean-values-in-conditions> official codestyle recommends
&gt; If you need to use a nullable `Boolean` in a conditional statement, use `if (value == true)` or `if (value == false)` checks.

<https://github.com/Kotlin/kotlin-style-guide/issues/18> not everybody agreed but I find it clearer to use `==`/`!=` because it makes it clear which of the 3 cases you are treating uniquely