Re: [BLACKBOX] Read-only IN parameters for all data types

From: [at]} <Aubrey.McIntosh{>
Date: Thu, 21 Feb 2008 09:31:48 -0600

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On Thu, Feb 21, 2008 at 5:43 AM, Oleg N. Cher <allot{([at]})nowhere.xy
> Dear Aubrey,
>

>
> By the way, so often it turns out, that a first sight at the Oberon
> is biassed. Why, do you think, so?
>

I notice this also. I have puzzled over it for a long time.

I just read the quote:
"There are two ways of constructing a software design: One way is to
make it so simple that there are obviously no deficiencies, and the
other way is to make it so complicated that there are no obvious
deficiencies."
--C. A. R. Hoare

and I put this quote together with one of my own personal experiences
from some time ago. In 1969 there was a model 33 teletype in the math
class in my (American) high school. It was connected to the GE
timesharing system, and offered FORTRAN and Algol-60. I learned both,
but had a strong preference for Algol, because I could comprehend it.

Another student and I ended up visiting GE and talking with some old
men. One of them became very interested when he learned that I liked
Algol and he asked why. I was too embarrassed to tell the real
reason, I did not yet have my ideas of conceptual accessibility, nor
the life knowledge that people who are really smart are the ones who
are unafraid to say "I don't understand." I am convinced that I
missed a great opportunity that day.

I think the seeds to understand are evident somewhere in that
anecdote, just out of my reach.

> >Here, if the programmer tries to assign an "in" variable, there are
> >design choices. One choice for the (language) design is that it is an
> >error. The other choice is that it is just a "free" scratch variable.
>
> >If you pass a pointer as IN, can you change the dereferenced data?
>
> Of course. Such use "IN" is represented probable.
> It describes the constant pointer, but the data which it specifies,
> can be changed. It can confuse a little, whether not so?
>
>

>
> This "serious ideas" are not, It's just a dream to have
> a possibility to write programs once, and build to be
> runned in any environment. All specific features must be
> hidden in appropriate modules, and all this will be
> penetrated with the general uniform interface.

I was very attracted to Oberon. I was having discussions someone who
would become my dissertation adviser and we talked in the framework
that writing allows the transmission of thoughts through both distance
and through time. This idea is "foundational." That is, it is an
idea underneath much of the discussions we have had.

Oberon came to my awareness in that epoch, and I had the sense that MY
DATA could be ported into the future on a CD ROM and I would continue
to be able to use it, even though the computers evolved and the
environment around me disappeared. This promise has been largely
realized. I have been reading a CD that I made in 1998 that has some
source and binaries for SPARC and SGI machines on them. I'm reading
it on an Intel machine. Things have finally become rational, in that
my data is the focus, and the machine is "only" an appliance.


>
> But people like to create own programming languages
> too strongly. May also I will create one Oberon subset? ;-)
>
>

Yes. When it was more obvious that I'm just a wannabe, I offered
advice to change the language to the newsgroup. These suggestions
came from others as well on a frequent basis. They were (properly)
very strongly rejected. Now, I have practiced some karate and have
been exposed to a discipline that has remained consistent across
millenia and which has a corresponding strictness about unauthorized
change. I think this discussion has the right balance --- not change
Oberon itself, and not change a dozen interaction design elements, but
look a one single change, implement it. The next step that I see in
the publications from ETH is to measure some system metric with both
options. I was looking at the .Obj file structure in "Project Oberon"
and Wirth laid out two possibilities to deal with the relocation
information on imported procedures. He did an astonishing thing: he
wrote two version of the compiler / linker and reported measurements.



>
>
> Oleg N. Cher,
> Colossoft Research.
> allot{([at]})nowhere.xy
> 2008-02-21
>

-- 
-- 
Aubrey McIntosh, Ph.D.
1502 Devon Circle
Austin TX 78723-1814
http://home.grandecom.net/~amcintosh/aubrey/Search/
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Received on Thu Feb 21 2008 - 16:31:48 UTC