[Aleph] otp's revisited

[Idris Samawi Hamid]

Hi friends,

Did anyone have a chance to look at the four experiments I sent a while 
back? Any comments?

Best to all
Idris

=========================Sat, 03 Jul 2004==========================
Subject: Four experiments [was Re: [Aleph] feature request :-))]
===================================================================

Hi to all in the cartel,

On Fri, 2 Jul 2004 02:07:52 +0200, Giuseppe Bilotta <gip.bilotta at iol.it> 
wrote:

> \expandafter\ocplist\expandafter\MyGreekOCP\expandafter=\MyGrOcps

> *will* work (correctly).

Below (in a single tex file) are four experiments
in laying the foundation for an
abstraction layer from ocplists and ocp primitives. The first
three use greek and the fourth uses arabic; all ocp's and fonts
are from the default (e-)Omega/Aleph distribution and do not
require LaTeX or ConTeXt; only (e-)Omega/Aleph.

In the following:

We use the expression `ocp-segment' to denote a set of one or more
\addbeforeocplist 1 lines; an ocp-segment is used in the creation
of an abtract ocplist that covers a certain set of parameters
needed to output a given script in a specific way;

We use `ocplist-segment' to denote a complete ocplist made from a
set of one or more \addbeforeocplist 1 lines; an ocplist-segment
is used to form an abstract string of ocplists, a string that
covers a certain set of parameters needed to output a given script
in a specific way.

First we do a static default greek setup: it works (of course);

Experiment one uses two ocp-segment abstractions from the greek ocps
with \expandafter s: it fails and also expands the `1' in
\addbeforeocplist 1 (it appears as a spurious `1' in the output);

Experiment two uses a single ocp-segment abstraction from the greek ocps
with \expandafter s: it fails

I played around with \expandafter in the above two case but could not
find a scenario that works:-(

Experiment three uses, not ocp-segments, but complete
ocplist-segments; it appears to work, but note that this case uses
only two \addbeforeocplist 1 lines; when more are added things
fall apart. See experiment 4;

Next we do a static default arabic setup: it works (of course;->);

Experiment four uses three ocplist-segments; it fails, except that
the Arabic-script numeral `4' is output.
But simple numerals do not depend on
the ocp transformations if they are mapped correctly in the font.

Question 1: why does experiment 3 _appear_ to work and experiment
4 fail? Clearly there must be something special about the third
case that does not get generalized to the fourth;

Question 2: what modifications are necessary to make experiments
1, 2, and 4 work?

I eagerly await your thoughts and suggestions

Best Idris

==============ocplist.tex==========================

% greek ocps
\ocp\GrTexUni=grpo2uni \ocp\GrUniToFont=uni2greek

%arabic ocps
\ocp\ArabUni=7arb2uni
\ocp\UniCUni=uni2cuni
\ocp\CUniArab=cuni2oar

% abstractions for greek
\def\GreekTranscription{\addbeforeocplist 1 \GrTexUni}
\def\GreekFont{\addbeforeocplist 1 \GrUniToFont}
\def\GreekFull{%
                \addbeforeocplist 1 \GrTexUni
                \addbeforeocplist 1 \GrUniToFont
                }

% default
\ocplist\GreekOcp=
                \addbeforeocplist 1 \GrTexUni
                \addbeforeocplist 1 \GrUniToFont
                \nullocplist

% abstraction xperiment 1 % expands the `1'
\expandafter\ocplist\expandafter\MyGreekOcpOne\expandafter=
\GreekTranscription
\GreekFont
\nullocplist

% abstraction xperiment 2
\expandafter\ocplist\expandafter\MyGreekOcpTwo\expandafter=
\GreekFull
\nullocplist

% abstraction xperiment 3

\ocplist\GreekOcpSegmentOne=
                \addbeforeocplist 1 \GrTexUni
                \nullocplist

\ocplist\GreekOcpSegmentTwo=
                \addbeforeocplist 1 \GrTexUni
                \nullocplist

\font\greek=omlgc at 12pt
\greek

%default
\pushocplist\GreekOcp

a b c d

% xperiment 1
\clearocplists
\pushocplist\MyGreekOcpOne

1 a b c d

% xperiment 2
\clearocplists
\pushocplist\MyGreekOcpTwo

2 a b c d

% xperiment 3
\clearocplists
\pushocplist\GreekOcpSegmentOne
\pushocplist\GreekOcpSegmentTwo

3 a b c d

% abstraction xperiment for arabic

% default
\ocplist\ArabicOCP=
\addbeforeocplist 1 \ArabUni
\addbeforeocplist 1 \UniCUni
\addbeforeocplist 1 \CUniArab
\nullocplist

% abstraction xperiment 4
\ocplist\ArabicOcpSegmentOne=
                \addbeforeocplist 1 \ArabUni
                \nullocplist
\ocplist\ArabicOcpSegmentTwo=
                \addbeforeocplist 1 \UniCUni
                \nullocplist
\ocplist\ArabicOcpSegmentThree=
                \addbeforeocplist 1 \CUniArab
                \nullocplist
\font\arabic=omarab at 12pt
\arabic
\textdir TRT\pardir TRT

% default

\clearocplists
\pushocplist\ArabicOCP

Aal-Hamdu Aal-Hamdu Aal-Hamdu

\blank[big]

% xperiment 4
\clearocplists
\pushocplist\ArabicOcpSegmentOne
\pushocplist\ArabicOcpSegmentTwo
\pushocplist\ArabicOcpSegmentThree

4 Aal-Hamdu Aal-Hamdu Aal-Hamdu

\bye

-- 
Professor Idris Samawi Hamid
Department of Philosophy
Colorado State University
Fort Collins, CO 80523