Kotlin: get a list of some property values from a collection / list of objects

Extension.kt

import kotlin.reflect.KMutableProperty1

inline fun <reified T, Y> MutableList<T>.arrayListOfField(property: KMutableProperty1<T, Y?>): ArrayList<Y> {
	val output = ArrayList<Y>()

	this.forEach {t: T ->
		@Suppress("UNCHECKED_CAST")
		output.add(property.get(t) as Y)
	}

	return output
}