Concept of a todo app in typescript's type system

gistfile1.txt

type List = string[];

type Add<T1 extends List, T2 extends string> = [...T1, T2];
type Remove<T1 extends List, T2 extends string> = T1 extends [T2, ...infer Rest]
  ? Rest
  : T1;

type Tasks1 = Add<[], "Task 1">;
type Tasks2 = Add<Tasks1, "Task 2">;
type Tasks3 = Add<Tasks2, "Task 3">;

type TasksToRemove1 = Remove<Tasks3, "Task 2">;
type TasksToRemove2 = Remove<TasksToRemove1, "Task 1">;