--- In qalam@yahoogroups.com, Marco Cimarosti <marco.cimarosti@...>
wrote:

> Richard Wordingham wrote:
> > You make it sound as though one needs to rewrite the operating

system!

> > 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?"

It would be a valid response to the statement that running the car
on vodka doesn't take rocket science.

> > > 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.

No, I meant vowels positioned (-pose-d) before (pre-) the consonant,
an issue you did address. (It would also apply to a nominally
subjoined 'r' in Lanna (clustered variant) and Khmer.)

> > 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).

This 'abnormal' case has generated many of the recent posts here!
And Tamil only has three preposed vowel symbols! Thai and Lanna
have five of them.

> 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.

Actually, I think it would be better to have a visible reminder that
a consonant is awaited.

Richard.