`requireNotNull` does not provide smart cast null safety. Is there another way to concisely mark nu...

# announcements

[Saiedmomen]

requireNotNull does not provide smart cast null safety. Is there another way to concisely mark null as Illegal state and have smart cast?

private var id: Long? = null

override fun delete() = runBlocking {
    requireNotNull(id)
    notesRepository.deleteNote(id!!) // id is not smart cast to not null
}

[Hasan Hosgel (alosdev)]

it would work if id is a parameter of the function or you put the result of require into an value and use it

[Petter Måhlén]

notesRepository.deleteNote(requireNotNull(id)) ?

[Nikky]

is id a var ?

[Nikky]

requireNotNull should smartcast, but it won't be able to for var that could change between the check and the usage

[Saiedmomen]

@Nikky Oh I see

[Nikky]

the id should tell you when you have a blocks like

if(id != null) {
    notesRepository.deleteNote(id)
}

it should warn you that it cannto smartcast id

[Nikky]

another way to solve similar problems is to assign them to a val in that scope
via let or similar scope functions

but best would be if you can get rid of the var .. or change it into a parameter.. which also makes it immutable in the scope of the function

[Saiedmomen]

@Nikky Yes that makes sense. thank you