Richard Wordingham wrote:

> You make it sound as though one needs to rewrite the operating system!

Yes, certainly. As I said at the end of my message, this is something that
should be implemented as system level, so I am talking about changing parts
of the operating system. Sorry if I haven't made this clear enough.

Of course, you can implement the same logic inside your own application.
But, then, of course, you cannot use the display or keyboard function
supplied by the operating system: you have to implement your own. It is
anyway necessary to rewrite a part of code which should be in the operating
system.

(Moreover, it is probably possible to invent hacks to simulate this behavior
on a system designed for logical-order. To obtain this, the insertion point
should sometimes be moved automatically before the last typed character is
inserted in a string.)

> To give a concrete example, how do I get IE to accept visual
> order? (I do not have a copy of its source code, let alone
> of Windows.)

Come on! :-)

If someone tells you that, in theory, it would be possible to design a car
engine which uses vodka instead of petrol, it doesn't make sense to ask:
"OK, so how can I put vodka in my car's tank?"

> > In logical-order input, when a reordrant character is typed, the
> software
> > inserts it in the "back store" and generates a fresh "visual store".
> >
> > In visual-order input, the process is reverted: when a reordrant
> character
> > is typed, the software inserts it in the "visual store" and
> generates a
> > fresh "back store".
>
> What would be done to the "back store" once you had entered a pre-
> posed character? I don't think this is a stupid question.

I guess you mean a "preCOMposed" character, and that what you have in mind
are those two-part vowels signs which display on both sides of a consonant.

If this is your question, no, in the "visual store" there is nothing
matching these kinds of characters.

Visually, a two-part vowel always corresponds to two separate glyphs, one
before the consonant and one after, consequently it would correspond to two
separate keystrokes in a visual-order input.

Of course, these precomposed characters could be generated when you create
the "back store" from the "visual store", but that would be something
invisible to users.

> It would have to
> be able to distinguish the sequence <consonant with inherent vowel> +
> <preposed vowel just entered> from the normal "back store" content of
> <consonant with inherent vowel> + <preposed vowel which will visually
> precede>.

If I understand what you mean, you are talking about a left-side vowel
visually at the end of a word. This is an abnormal case which should only
occur temporarily while typing a word (or when one forgets to end typing a
word).

The only way I see to map this to logical-order is to insert an invisible
character between the consonant on the vowel mark. I can be discussed which
one of the many existing "zero-width" characters would be more appropriate
to do this.

--
Marco