New vc and Mercurial (hg)?

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    Ville> If someone wants to have a look at porting vc-hg.el to XEmacs and
    Ville> replacing mercurial.el in the vc package with ot or look at what
    Ville> would it take, please go ahead.  If the switch is going to be
    Ville> made, it'd be better to do it now while the new vc package is in
    Ville> the experimental area rather than later.  I may get to it
    Ville> sometime, but that's not a promise and it's not likely to happen
    Ville> any time soon.

Is there some "institutional knowledge" which tells what common changes to
look for when porting from GNU Emacs to XEmacs?

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