Re: Fwd: overlay face property not used for after-string property

[Richard Stallman <rms@gnu.org>]

    I think priorities are probably the solution.  Here is an idea.  Each
    face property and each piece of text has a priority.  A face property
    can only affect text of strictly lower priority.  The before-string,
    display (if a string), and after-string properties of an overlay have
    the priority of their overlay.  Text in the buffer has priority 0.
    The face property of an overlay has the priority of that overlay.  A
    text property face property (i.e., in a string or in the buffer) has
    the priority of the piece of text plus 0.5 (so that it will affect the
    text it belongs to).

It sounds plausible.  Could you figure out how you would use this and
verify that it would give correct results in the cases you know about?