Here is how you can unwrap optional variable in Kotlin

Let / Also

You can use a lambda function let / also to safe unwrap the optional variable.

(Assume plant is the optional variable)

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plant?.let {
    it.height = 20
    displayGrowStage(it)
}

Use a different Parameter other than it

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plant?.let { plant ->
    plant.height = 20
    displayGrowStage(plant)
}

Return If Null

In Swift, you have guard let xxx = xxx else to unwrap the optional variable. So here is the similar thing I will do in Kotlin.

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val plant = nullablePlant ?: return
plant.height = 20
displayGrowStage(plant)