I am looking to define an override function in a class using TypeScript, but only for certain browsers. I don't want to have to implement browser checks everywhere and call some derived class, I would prefer to just define an override, but only for certain conditions. So far, the only way I have found to accomplish this is by using a library called jTypes, but I would really like to know the answer to this question, seeing as how many of my projects are all using TypeScript, and I don't really want to have to port all my existing code. Thanks.