How do I initialize Kotlin's MutableList to empty MutableList?

Question

Seems so simple, but, how do I initialize Kotlin's MutableList to empty MutableList?

I could hack it this way, but I'm sure there is something easier available:

var pusta: List<Kolory> = emptyList() var cos: MutableList<Kolory> = pusta.toArrayList() 

Answer 1

You can simply write:

val mutableList = mutableListOf<Kolory>() 

This is the most idiomatic way.

Alternative ways are

val mutableList : MutableList<Kolory> = arrayListOf() 

or

val mutableList : MutableList<Kolory> = ArrayList() 

This is exploiting the fact that java types like ArrayList are implicitly implementing the type MutableList via a compiler trick.