Method union

src/main/java/net/starlark/java/types/Types.java:351–353

Constructs a union type. If the types sets contains another Union type it's flattened. Duplicates are removed. If types set contains Object type it's simplified to Object type. If the set contains a single element, it is returned instead of constructing a union. @throws IllegalArgumentExcep

(StarlarkType... types)

   * @throws IllegalArgumentException If an empty set is passed in.
   */
  public static StarlarkType union(StarlarkType... types) {
    return union(ImmutableSet.copyOf(types));
  }

  /** Constructs a union type. */
  public static StarlarkType union(ImmutableSet<StarlarkType> types) {