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kotlinlang

Why is `by` used instead of assignment at
```var isSelected by remember { mutableStateOf(false) }```
I’m following Google’s codelab

I am just a beginner, so take my response with a grain of salt.

`mutableStateOf(T)` returns a `MutableState&lt;T&gt;` object where the value is stored in `MutableState&lt;T&gt;.value`

So, if you don't want to use `by`, your code would look like this:

```val isSelected = remember { mutableStateOf(false) }
```
To retrieve state, you need `isSelected.value` And to change state, you would do this:

```isSelected.value = true
```
Using `by` you can tell Kotlin to use the getter and setter function of the state (you need some extra imports for this functionality) whenever you get or set the value of the variable `isSelected` Those getter and setters would modify the `value` parameter of the state object under the hood.

In other words, instead of `isSelected.value` you can just use `isSelected`

To change `isSelected`, instead of the previous code, you can simply write

```isSelected = true
```
Tldr: Using `by` keyword, you can simply treat the mutable state object as a normal variable.