Re: Native display of line numbers

[martin rudalics]

> Btw, the stuff that really bothers me are all those low-level
> functions that depends on window geometry for measuring the text-area
> width.  Line numbers take up some of that space, and it isn't clear to
> me what that breaks.  Perhaps you could take a look at the relevant
> functions?  We may need to provide a primitive which returns the width
> taken by the line number display.

If you intend to keep the current implementation, I see no need for such
a primitive.  The window code doesn't handle ‘line-prefix’ or
‘wrap-prefix’ specially either.  Things will get problematic as soon as
you want to display line numbers outside the fringes or margins.  But
IIUC you currently don't have any intentions to do that.

If someone wants the mouse to do something special on line numbers, then
coordinates_in_window would have to be amended appropriately.  Whether
we want to consult the current glyph matrix in that case or keep a LorR
bool + a line_number_display_width integer in the window structure is a
minor issue IMHO.  Maybe a boolean to turn off line numbers for a
specific window only would be useful.  This can be easily added later.

martin