Code review comment for lp:~alan-griffiths/mir/add-mir_surface_spec_attach

> I suppose there's also the issue of how easy things are to understand (which
> naming and typing helps with). I'd rather see two needs fulfilled by two
> different easy-to-understand functions than two needs fulfilled by one harder-
> to-understand function. It seems that we don't really know the future
> enhancements, so I'd rather just see
>
> mir_surface_spec_attach_relative(MirSurfaceSpec*, MirPlaceMode, MirRectangle*)

You mean mir_surface_spec_attach_relative(MirSurfaceSpec*, MirEdgeAttachment, MirRectangle*)

>
> without reserving the upper bits of the mode as opcodes that alter what the
> function does

That was motivated by skimming https://blog.gtk.org/2016/07/15/future-of-relative-window-positioning/ and https://bugzilla.gnome.org/show_bug.cgi?id=756579#c311