Hello, can i define a lambda that accepts a mutab...

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[otakusenpai]

Hello, can i define a lambda that accepts a mutable variable as parameter?

[Dico]

You want to be able to modify a variable that's passed into the lambda from the lambda?

[otakusenpai]

yes

[otakusenpai]

val bbToString = { bb: ByteBuffer, d: String -> d = String(bb.array(), Charset.forName("US-ASCII")) }

[Dico]

You can't do this in Kotlin

[otakusenpai]

ok then

[Dico]

If you must return multiple values, you can use Pair<> or a data class

[Dico]

You can also modify any variables in the scope of the lambda, of course

[otakusenpai]

ok gotcha

[Sam]

@otakusenpai You could pass by reference via AtomicReference or use StringBuilder etc

val lambda = { s : AtomicReference<String> ->
    s.set( "updated string" )
}

fun main( argv : Array<String> ) {
    val string = AtomicReference<String> ("initial value")

    println( string )

    lambda( string )

    println( string )

}

[Sam]

Here the reference is passed by value but you are working with what is being referred to