IDE that uses an external editor?

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    >> #> I realize I can do a lot within Emacs/XEmacs, but I suspect with a
    >> #> tool like Eclipse I could do more. However, I don't want to give
    >> #> up the text editing power of Emacs to get it.
    ...
    Ramon> I've tried using Eclipse several times, because several good
    Ramon> meaning people told me things like "you coud do more". 

My observation about Eclipse comes simply from watching one of the other
developers at work use it.  I'd like to give it a try, but not at the
expense of giving up Emacs.

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