Is anyone could help with this: How to write an ex...

# announcements

[mike_shysh]

Is anyone could help with this: How to write an extensions function if data class is defined in .kt file, not in kotlin separate class

fun CustomerInfo.addRandomPartToName(): CustomerInfo {
    val oldItem = this.customerInfo <<<< `this` is not usable
    val newItem = oldItem?.copy(name = oldItem.name + RandomStringUtils.randomAlphabetic(7))
    return this.copy(customerInfo = newItem)
}

[menegatti]

what’s the error message?

[menegatti]

it seems to me that oldItem should be only this as that is the scope of your extension

[mike_shysh]

Error:(27, 24) Kotlin: Unresolved reference: customerInfo

[mike_shysh]

Error:(29, 22) Kotlin: Cannot find a parameter with this name: customerInfo

[mike_shysh]

customerInfo is red

[mike_shysh]

val oldItem = this.customerInfo

[mike_shysh]

this.copy(customerInfo = newItem)

[menegatti]

the thing is this is already CustomerInfo

[mike_shysh]

oh sorry, my bad

[mike_shysh]

yeah, data clases names were a bit messed up

[menegatti]

this will always be the instance of the type to which the extension belongs to

[menegatti]

fun String.foo() = this.append("a") for instance

[mike_shysh]

thanks, got it