```var data by useState<List<MessageTemplate...

# javascript

[Pitel]

var data by useState<List<MessageTemplateDto>>()

useEffectOnce {
  MainScope().launch{
    data = someSuspendingFetch()
    console.log(data) // undefined?!
  }
}

makeTable(data) // renders table with data

WTF?! Why is data right after assigning it someSuspendingFetch() undefined, and yet it renders table with them.

[turansky]

It’s useState nature 🙂

[turansky]

Performance recommendation - use Array instead of List

[turansky]

useState delegate - just useful wrapper

Standard case:

val (count, setCount) = useState(0)

useEffectOnce {
    setCount(1)
    println(count) // 0
    setCount(2)
    println(count) // 0
    setCount { prev -> 2 * prev } // 2 * 2 = 4
    println(count) // 0
}