eshell: Support old-style completion and cycling completion?

[kai.grossjohann@uni-duisburg.de (Kai Großjohann)]

Usually, I know and love the fact that hitting TAB completes as far
as it can, then offers the list of completions.

But sometimes, I think it might be nice to cycle the completions
instead.  So I tried a naive approach:

(defun kai-eshell-pcomplete-cycling ()
  "Like `pcomplete', but turn on cycling explicitly."
  (interactive)
  (let ((eshell-cmpl-cycle-completions t))
    (pcomplete)))

Then I bound this to a key.  No dice.

Hm.  Thinking some more, it's possible that a behavior that I would
like is this:

If there is a common prefix for all completions, insert that.  If
there is more than one possible completion, beep.  After the next
TAB, show all possible completions.  After the next TAB, complete to
the first completion.  So it's a kind of a hybrid between old-style
and cycling style.

But I don't have this behavior, so I haven't tried it, so I don't
know.  What do people think?
-- 
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