is there a way to resolve an ambiguous += to a list?

cliOptions += CliOption()

clioptions is a java List

Assignment operators ambiguity. All these functions match.
public operator fun <T> Collection<CliOption!>.plus(element: CliOption!): List<CliOption!> defined in kotlin.collections
public inline operator fun <T> MutableCollection<in CliOption>.plusAssign(element: CliOption): Unit defined in kotlin.collections

You could do

cliOptions.add(CliOption())

or

cliOptions = cliOptions + CliOption()

depending on the one you want

not always but often

var : MutableList

is a poor design choice anyway

@Joffrey why do i have to do

= +

? this doesn't really answer why += doesn't work, and why i have to explicitly call assignPlus()

.plusAssign

and

= .plus

are the respective meanings of

+=

with

val cliOptions: MutableList

and

var cliOptions: List

respectively. but if you have a

var cliOptions: MutableList

then

+=

is ambiguous