Re: Insert character pairs

[Richard Stallman]

    I propose to bind `rise-up-list' to currently unused `C-x C-M-u'.
    The reason is that it is similar to `backward-up-list' (`C-M-u'),
    but with the prefix C-x will move the list backward out of one level
    of parentheses instead of moving the point as `backward-up-list' does.

It is true that sometimes we use C-x for a related command.  But this
feels not quite right.  Partly that's because we have no bindings on
C-M- characters after C-x.  (Such combinations are a little hard to type.)

It is an acceptable choice, but I think we should first try to look at
other options.  If we can't find anything better then let's use C-x
C-M-u.