Re: Framework extending window functions for Follow Mode (etc.).

[martin rudalics <rudalics@gmx.at>]

 > The six functions window-start, window-end, set-window-start, recenter,
 > pos-visible-in-window-p, and move-to-window-line-function will acquire
 > an extra optional parameter GROUP.  The notion is that "this call is
 > interested in groups of windows, not just single ones".
 >
 > Each of these functions will get an associated variable, e.g.
 > "window-start-function".  The function will call the value of that
 > variable instead of doing its normal actions, when GROUP is non-nil.
 > Typically, the `window-start-function' will recursively call
 > window-start (on some window) to perform its operation.

Instead of an extra argument I would prefer to have these functions
check for the presence of a ‘window-start’, ‘window-end’, ... window
parameter just like ‘delete-window’ or ‘other-window’ do.

martin