Just finishing integrating hookrouter into my current project. I like it a lot so far! Very easy to implement and reason around. On a certain page my user is f

Just finishing integrating hookrouter into my current project. I like it a lot so far! Very easy to implement and reason around. On a certain page my user is filling out a form, and I want to confirm before they can leave, to prevent loss of unsaved data. I think it would be better if this was baked into the package somehow. I'd want something simple where you could set it for a whole page and it applies to children and parents. I also would prefer to be able to pass any function, in case window.confirm() isn't good enough.