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What standard delegates do you know?

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Answer from AI

by lazy — used for deferred initialization of a property. The value is computed upon the first access to the property and cached.
```
val lazyValue: String by lazy {
    println("initialized") // Executes only on the first access
    "Hello"
}
```

Delegates.observable — a delegate that allows executing an action every time the property's value changes.

import kotlin.properties.Delegates

var name: String by Delegates.observable("initial value") {
    prop, old, new ->
    println("Value changed for ${prop.name} from $old to $new")
}

Delegates.vetoable — a delegate that intercepts changes to a property's value and can cancel the change based on a condition.

import kotlin.properties.Delegates

var age: Int by Delegates.vetoable(10) {
    prop, old, new ->
    new >= 0 // Only allow non-negative values
}

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