action.names.ts

class ActionNames {
  private static names = new Set<string>();

  static create(name: string): string {
    if (ActionNames.names.has(name)) {
      throw new Error('An Action with this type already exists!');
    }
    ActionNames.names.add(name);
    return name;
  }
}

const someAction = createAction(ActionNames.create('[Page] Actions Name'));