Combining List and Non-Null

List and Non‐Null can compose, representing more complex types.

If the modified type of a List is Non‐Null, then that List may not contain anynullitems.

If the modified type of a Non‐Null is List, thennullis not accepted, however an empty list is accepted.

If the modified type of a List is a List, then each item in the first List is another List of the second List’s type.

A Non‐Null type cannot modify another Non‐Null type.