armanriazirustsmartpointerboxcons

cons=recursive type
We now know that any List value will take up the size of an i32 plus the size of a box’s pointer data. By using a box, we’ve broken the infinite, recursive chain, so the compiler can figure out the size it needs to store a List value.
Cons+Box :A List that is not infinitely sized because Cons holds a Box
Cons : A List that is infinitely sized because Cons holds a Box.
Cons is just a name and it is replacable with anyname
ArmanRiazi