Question

What will be the result of comparing empty lists (Nil)?

val a: List[String] = Nil
val b: List[Int] = Nil

a == Nil // 1
a eq Nil // 2

b == Nil // 3
b eq Nil // 4

a == b // 5
a eq b // 6

Cosmo · Accepted Answer

Nil is defined as following:

case object Nil extends List[Nothing]

Nil lists are identical, even of different types.

Cosmo · Accepted Answer

Everything is true

Cosmo · Answer

Everything is false

Cosmo · Answer

1, 3, 5 - true; 2, 4, 6 - false

Cosmo · Answer

1, 2, 3, 4 - true; 5, 6 - false