[R] help went away from top emacs window :-(

[Richard M. Heiberger]

I located what might be the problem.  There is a different misbehavior
with Gnu emacs.  I don't have Xemacs.  I have an idea how to fix it but
haven't worked out the details.


ess-inf.el in the lines
(defconst inferior-R-1-input-help (format "^ *help *(%s)" ess-help-arg-regexp))
(defconst inferior-R-2-input-help (format "^ *\\? *%s" ess-help-arg-regexp))
(defconst inferior-R-page	  (format "^ *page *(%s)" ess-help-arg-regexp))

detects help requests from the commandline in the *R* buffer and redirects
their output to an emacs *help[R] (whatever)* buffer.

In gnu emacs on windows, with options(chmhelp=TRUE), the effect is an empty
*help[R] (whatever)* buffer.  What I think happened is that ESS trapped the
request and created the buffer, then R never got the right content to send
to that buffer because R thinks that chm is handling it.

The fix probably requires ESS to check the value of the chmhelp option
and suppress the interception of help requests if the option has the value
TRUE.  ESS also needs to monitor if that option has been changed.  This might
mean that ESS always intercepts help requests and checks the value of the option
each time.

Rich