Michael wrote:

> At 15:36 -0700 2003-06-26, Kenneth Whistler wrote:
> 
> >I now like better the suggestions of RLM or WJ for this.
> 
> ZZZZZZZT. Thank you for playing.
> 
> RLM is for forcing the right behaviour for stops and parentheses and 
> question marks and so on. Introducing it between two combining 
> characters in Hebrew text would break all kinds of things,

True, apparently, but not for the reasons you surmise.

RLM does not "force behavior" on things. It is a strong
right-to-left context that can change the resolved directionality
of neutrals or weak types next to it. In between two
characters that are already R, the presence or absence of an
RLM is basically a no-op for bidi.

Just considering the bidi algorithm, a sequence:

  <lamed, patah, RLM, hiriq>
     R      NSM   R     NSM
  
would have the resolved directions: <R, R, R, R>, effectively no
different than the resolved direction: <R, R, R> of the sequence
without the RLM.

The problem arises when you go to consider the graphic application
of the combining mark to its base form, and for that, the issue
is apparently the same for the WJ, ZWJ, or any other format
control in such a position. So this is nothing to do with the
bidi function of RLM. 

> and would 
> be horrible, horrible, horrible. Invent a new control character for 
> this weird property-killer, if you must, but don't use an ordering 
> mark for it

If you invent a "new control character" for this "weird property-killer"
(which it wouldn't be, since in any case, I'm just talking about
inserting a (cc=0) character in between two other characters, not
changing or killing any properties), you still end up with exactly
the same problem of graphic application, because the
presence of any format control creates a defective combining
character sequence which applications (apparently) won't display.

--Ken



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