Re: before- and after-string issues

[Richard Stallman]

    Putting `mark' before S and `point' after T highlights the entire
    overlay but not its after-string.

That in itself might be ok.

                                       Placing `mark' after T and `point'
    after the character following T does not highlight a single character of
    O but does highlight the after-string.  This is counterintuitive.

That is clearly a bug.

    Moreover, A inherits face properties from the character displayed after
    A and not from the last character of the overlay.  Counterintuitive too.

I don't see why A inherits any properties from characters either before
or after it.  That seems like a bug.

Normally when we speak of inheriting text properties we mean that you
insert character C and it gets properties from an adjacent character
D.  But that doesn't happen here, does it?  Do you actually mean
that the text of A is displayed in a way controlled by the properties
of the following character?

That seems to be simply a bug.  So I think we don't need to look
for adding some kind of new features, some kind of "barriers".
We just need to fix the bug.

    that is, the before-string is displayed twice with the cursor after the
    second incarnation.  Redisplay removes the double.

That is also simply a bug.

You've found an awful lot of bugs.  Thank you.
Now we have to try to fix them, which won't be easy.
But at least we have the possibility to try.