bug#1503: feature request: multiline header (and mode) lines

[martin rudalics]

> One benefit of the header line is that it always stays in place, whereas
> with a buffer you never know where it might end up.  Or is there a way
> to force a buffer in place with the same strong guarantee?

Why not?  Have you ever seen windows deliberately change places on a
frame?  Atomic windows are glued together like a window and its mode
lines.

> We also might not want users to switch to that buffer, as it would be
> more annoying than useful (e.g. headers in tabulated-list-mode).  AFAIU,
> with a regular buffer you will always be able to switch to them with
> `other-window'.

That's what the 'no-other-window' parameter is for.  With the slight
difference that with a window you can turn it off temporarily.

> I was also going to say that with header-line-format you get horizontal
> scrolling automatically, but it turns out that you don't.  In any case,
> it seems like this feature shouldn't be too hard to add.  (I remember
> now that I added code to fix that in one of my packages.)

XEmacs has it, IIRC.

martin