Is it possible to catch an event when typeahead field is emptied or no match is found?

[marceloverdijk]

And if not do you think it's possible to add feature for this.

What I would like implement is a standard select like typeahead, where the user can only select values form the source.

Next to that I need to catch an event if the typeahead is emptied as based on the selection I'm setting some other values. Think of source is a product catalog, where after selecting an item the price is also retrieved from the source and stored in another field.