I might me missing something obvious here but I'm ...

# getting-started

[Jukka Siivonen]

I might me missing something obvious here but I'm trying to introduce nullable function parameter like

fun <T : Any?> execute(queryId: (() -> UUID)? = null, operation: Operation<T>): T? {

but I can't invoke this by

execute(Operation(...))

only

execute(null, Operation(...))

works, any pointers?

[diesieben07]

You can only leave out trailing optional parameters, not leading ones. If you just want to pass the operation parameter you need to use named-parameters when calling:

execute(operation=Operation(...))

[Jukka Siivonen]

Ah, thats correct. Thanks.

[Matteo Mirk]

so following this language rule you could move the lambda to be the last parameter, then you could call the function like this:

execute(Operation(...))

or

execute(Operation(...)) {
    // new uuid
}