hi, is there more documentation on contracts? i’ve...

# announcements

[Hamza]

hi, is there more documentation on contracts? i’ve seen a bit of stuff, but not sometthing like what i am looking for. is that trying to confirm all of the varargs provided aren’t null:

@UseExperimental(ExperimentalContracts::class)
fun anyNotNull(vararg arguments: Any?, block: () -> Unit): Boolean {
    contract {
        returns(true) implies /* Something here that tells the compiler that all arguments are not null */
    }
    if(arguments.any { it == null }) {
        block()
        return false
    }
    return true
}

[gildor]

not sure that it’s supported. Probably KEEP is the best source of information about contrcats

[Hamza]

kk

[Hamza]

could i do something like this?

inline fun anyNotNull(vararg arguments: String?, block: () -> Unit) {
    if(arguments.any { !isNotNull(it) }) {
        block()
    }
}

@UseExperimental(ExperimentalContracts::class)
fun isNotNull(arg: String?): Boolean {
    contract { 
        returns(true) implies (arg != null)
    }
    return arg != null
}

[Hamza]

aww, it didn’t work

[gildor]

Maybe you could ask here: https://github.com/Kotlin/KEEP/issues/139

[Hamza]

kk