Re: local keymap patch for key-binding

[Richard Stallman]

     (`key-binding' can't be used to look up events, and I am less
    than certain that it should).

Of course key-binding can be used to look up events.  If you want to
look them up in the current active keymaps, key-binding is the natural
way.  The recent change affects the lookup of events that specify
positions.  It has no effect on what happens if you pass a list of
event-types without positions.

Perhaps there is a misunderstanding here about what it means
to "look up events".

    a) add an additional optional parameter BASE-KEY which, when non-NIL,
    will replace KEY for all purposes of lookup except determining the
    keymaps to use when KEY is a key-sequence based on an event.

I don't follow this at all, sorry.

    b) have a function `event-replace-key' or something with a better name
    which will take a key sequence based on an event and swap out the
    basic event (but maybe _not_ its modifiers since they can play a part
    in which keymap to use) and swap out the `down-mouse-2' or similar
    with `follow-link'.

What does "swap out" mean here?