Ruthven said:
Yeah, just a sort of "melee" key like in shooter games.
That could also work with clubbing somebody with a bow.
I think an archer would have to be very desperate before he started clubbing people with his bow. A bow is under constant tension and needs to be handled with care for it not to break or crack.
But you should be able to quickly pull your melee sword without putting away your bow; after all, the bow is held in the less favoured hand, so you would have to switch hands to get control and force behind your bow-clubbing, should you choose to use that method. Have a short sword in a sheath along with your quiver on your back, so that you can draw it quickly using the same automated movement you've trained up for fast firing.