Typescript Generics Example (http://ideasof.andersaberg.com/)

Generics Example

class MyApp {
    constructor() {
        var myUsers = new CustomCollection<User>();
        var myMessages = new CustomCollection<Message>();

        myUsers.Add(new User());
        myMessages.Add(new Message());

        var user: User = myUsers.GetFirst();
        
        // Error because of generic type validation
        var message: Message = myUsers.GetFirst();
        // Error because of the Generic type validation.
        myUsers.Add(new Message()); 
    }
}

class User {
    public Name;
}
class Message {
    public Message;
}

class CustomCollection<T> {
    private itemArray: Array<T>;

    constructor() {
        this.itemArray = [];
    }

    Add(item: T) {
        this.itemArray.push(item);
    }

    GetFirst(): T {
        return this.itemArray[0];
    }
}