I know that val cannot be reassigned but how would I for exa

Question

I know that val cannot be reassigned but how would I for example send a variable to a function to do something with it ```private fun resetCounterAndGame counter Int if counter == 2 gameButtonText set resProvider getString R string try another number gameStarted = false counter = 0 lt val cannot be reassigned of course ```

wbertan · Answer

Can you make it return the new value for `counter`

oday · Answer

yea sure I can but then I would be doing `thingImTryingToCount = resetGameAndCounter thingImTryingToCount `

oday · Answer

right

oday · Answer

yea cause I wanna do this for several counters

oday · Answer

I think the function is doing too much

oday · Answer

I can have an extension function that can be like `counter reset ` and if `this == 2 return 0 else return this`

wbertan · Answer

Could you use a `MutableStateFlow` instead So you can pass the reference and set a new value and whenever reads the state flow would always pick the latest value

oday · Answer

hm im not really using coroutines right now

oday · Answer

ill check it out

Vampire · Answer

Your problem is not so much that `val` cannot be reassigned but that you confuse pass by value and pass by reference

Vampire · Answer

You don t push a variable to the method but only its value

Vampire · Answer

In case of an object you are passing the reference to that object in and can modify the state of that object

Vampire · Answer

But for an `Int` you just pass the `2`

Vampire · Answer

You can probably do something like this ```private fun resetCounterAndGame counter KMutableProperty lt Int gt if counter getter call == 2 gameButtonText set resProvider getString R string try another number gameStarted = false counter setter call 0 ``` and then pass the reference to the field with `resetCounterAndGame counter ` or similar but I would strongly advice to not do this

Tobias Berger · Answer

there are some ways you could do this you could return an object containing all the new values you want to set and do so after the function call you could pass setter callbacks to the functions that set a new value when called you can wrap the mutable values in an object that is passed to the function and then modified inside Depending on your use case each of these can be the perfect solution or a real code smell

Tobias Berger · Answer

actuall I also thougt of the KMutablePropert approach I wouldn t sa it s a no go especially since reflection in Kotlin offers a lot more type safety than in Java But it can still have some performance impact which might be undesireable in a mobile application and also it would only work with properties not with local variables

Vampire · Answer

Yeah probably better to give a setter instead of using reflection but still a bit smelly smile ```private fun resetCounterAndGame counter Int counterSetter Int gt Unit if counter == 2 counterSetter 0 fun main var counter = 1 println counter resetCounterAndGame counter++ counter = it println counter resetCounterAndGame counter++ counter = it println counter ``` = gt ```1 2 0```

Kirill Grouchnikov · Answer

Ah the good old Fortran days where you could pass 4 as an integer argument and then the function could override its value to 5 Then after the function returns everywhere you had 4 was treated as 5 Yeah you don t want that

Ryan · Answer

use an AtomicInt