Re: help-window-select and info-lookup-symbol

[martin rudalics <rudalics@gmx.at>]

 > It seems to me that C-h S and C-h f are so similar that both commands
 > should honor the value of help-window-select.  In fact, there are a lot
 > of (third party) packages with a display-documentation-in-other-window
 > command but there seems to be no agreement whether the window should be
 > selected or not.  Especially annoying is the fact that XEmacs usually
 > selects the other window while Emacs usually does not.

C-h f is a self-contained function while C-h S falls back on `info' for
displaying its findings.  Obviously, a common approach to handle these
and similar cases would be desirable.

 > It would be very nice if you, the Emacs maintainers, could make a rule
 > or style-guide how this should be done.  E.g. should other packages look
 > at help-window-select or is that an "internal" variable of help-mode?

Currently `help-window-select' is an "internal" variable of help-mode.

 > I understand that restoring the window configuration after pressing q in
 > the help window (or info window, or w3m buffer) is sort of tricky and it
 > gets very complex if multiple frames are involved, yet selecting the
 > help window is what many users expect.  Since restoring is so tricky it
 > would also be helpful if there were some general functions to do it
 > properly.

Restoring an old window configuration is awfully tricky.  Let W1 denote
the window configuration before invoking help, W2 the configuration
after invoking help (and after any `fit-window-to-buffer' and balancing
stuff), and W3 the configuration when you press `q'.  A brute force
approach (currently used by info or backtrace) simply restores W1 whe
you press `q' which all so often drives me mad because it destroys the
windows and window-buffer associations I have created in between.

Now theoretically, I could restore W1 if and only if the configurations
W2 and W3 are equal.  In practice, however, this approach often failed
here.  Hence, I tried to base the comparison on a weaker predicate of
equality which ignored the identities of buffers displayed in other
windows and the relative sizes of windows.  I got it to work for help
buffers but was not able to make it work realiably with info buffers.

martin