I have a

mutableListOf<Pair?>

that I want to check the contents of. I try something like this on Kotlin 1.5.21:

fun foo(value: List<Pair?>): Boolean {
        return list.contains(value)
    }

I get the following error:

Type inference failed. The value of the type parameter T should be mentioned in input types (argument types, receiver type or expected type). Try to specify it explicitly.

I can remove the error by modifying it to

return list.contains<Any?>(value)

but it feels like a weird work around. Anyone got insight as to the best way to approach this?

a

(Mutable)List<Pair?>

should never contain a

List<Pair?>

element. do you mean

containsAll

?

The snippet infers that

list

is

List<List<Pair?>

.

.containsAll

would check that all elements of

value

are also elements of

list

, where the two are both

List<Pair?>

interesting kotlin 1.4.0 didn't flag it as a compile-time error