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

[Stefan Kangas]

martin rudalics <rudalics@gmx.at> writes:

>> Can emacs be given the gift of a header-line that word wraps, so that
>> the header can be more than one line tall?  I imagine the same could
>> go for the mode line, but I don't have a clear need for that right
>> now.  I know that the fringes can occupy > 1 column, so it seems like
>> an oversight if the header and mode lines are restricted to 1 line.
>>
>> I've written a minor mode for reading/sorting physics abstracts from
>> the physics arXiv.  The mode either lists subdirectories directly
>> under the current directory, or recursively lists all subdirectories
>> of the pwd.  Either way, the list could potentially be longer than the
>> width of the screen, making some directory names unviewable.  A
>> multiline header would make it perfect.
>>
>> I thought of putting that text in the buffer, but that makes it much
>> harder to update the text.
>
> At the moment, we can't do that because the fact that a header-line
> occupies exactly one line of text is hardwired into many lower-level
> primitives.

Could those primitives be changed to support this use-case?

I'm not very interested in a multi-line mode-line myself, but I can see
many uses for a multi-line header line.