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```data class Car(val name: String) @Composable p...
# compose
t
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data class Car(val name: String)

@Composable
private fun Test() {
    var car by remember { mutableStateOf(Car("Audi")) }
    var remCar = remember { car }
    LaunchedEffect(car) {
        remCar = car
    }
    println("remCar is `${remCar.name}`")
    Button(
        onClick = {
            car = Car("BMW - ${System.currentTimeMillis()}")
        }
    ) {
        Text("CHANGE CAR")
    }
}
Pressing 
CHANGE CAR
button always prints 
remCar is Audi
Why it’s not printing 
BMW
? 🤔
✅ 1
j
Because you remember a value that is captured once
You need to use derivedStateOf
or add 
car
as a key to the second 
remember
oh i missed the 
LaunchedEffect
, but it's not a 
State
so writes to it presumably won't trigger recomposition
t
Yeah, but it should print 
BMW
for the next recomposition, right?
j
It will not because when the function re-runs the 
remember
will re-read the original 
car
value from the slot table and it will always reset to the Audi
t
Ooo 😮 So basically, we can’t change a 
remember
-ed value like this
j
That's right. Because it's basically a positional marker into a separate storage mechanism. All you do when you overwrite the local is overwrite the value that was read. You do not overwrite the backing storage location.
k
It won't work because changing the value of 
remCar
is not actually changing the value of the 
mutableStateOf
, that's a misconception because the setter of 
car
is not actually just setting a variable but updating the state, also you don't need to remember 
car
, it's been already remembered.
j
When you remember a 
State
the backing storage contains a reference to the 
State
instance rather than a raw value. This is why changes to the 
State
are reflected on future recompositions. The 
remember
reads out the same 
State
instance each time but the value held by that 
State
is what changes.
t
Ohhkay.. Understood. Thank for the explanation guys 🙌
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