COM-EDIT-DEFINITION extension

[Mike McMahon <MMCM at MIT-AI>]

this is definitely a useful thing to be able to do, but i am not sure this is the right
way to do it.
minor problems with the way you have it are that the list grows and grows and should probably
have a maximum size; typing errors also get pushed onto the list, even though the call
to EDIT-DEFINITION bombs.
it is also a fair amount of overhead to bring up the mini-buffer when you only want to type CR
at it (you already have the right idea of what the default will be).
also this does not save functions that you got to from edit callers, function apropos and
friends.
i think it might be much better to orient this around the point pdl, with some command to go to
the last position in that and push point.
does anyone else have ideas?