Is there a way to check if a `lateinit var func: () -> Unit` has been initialized? Or, if there’s...

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[rook]

Is there a way to check if a lateinit var func: () -> Unit has been initialized? Or, if there’s a better strategy for this, I’m open to other solutions.

[Aleksa Boškov]

::func.isInitialized

[streetsofboston]

Still, use isInitialized with caution.

I’d use either a nullable var:
var func: (() -> Unit)? = null

or a lazy one, where it will be initialized lazily given the class’ dependencies:
val func: () -> Unit by lazy { /* create value for func */ }

[streetsofboston]

(if you have set-up your dependencies (of the class that contains the val func) correctly, using by lazy should work fine)

[rook]

There are a list of lambdas that can be optionally defined, and based on whether they’re supplied by a consumer, it will change the resulting object’s functionality. This makes by lazy not an option. But I think the nullable field is probably a better route.

[dam5s]

Sounds right.

lateinit is not designed for things that may not be set, it's definitely for values that you know will have a value the first time you access them.

[streetsofboston]

I reserve lateinit only for classes whose lifecycle is not under your control and are initialized on a callback later (eg onCreate(...), initialize(...) calls, dependency @Inject, etc).