Julian Leviston | 1 Sep 03:42 2011
Picon

Re: More information about the "text layout engine for paragraphs" in VPRI Tech Report

vpri.og is working for me.

Are you talking about Gezira/Nile?

http://www.vpri.org/vp_wiki/index.php/Gezira

Julian

On 01/09/2011, at 5:40 AM, nchen.dev@... wrote:

> Hi
> 
> I briefly remember Alan and other members of VPRI doing a presentation of the text layout engine while they
were here for a short visit to the University of Illinois at Urbana-Champaign. I'm currently dealing with
some layout work in Morphic and would like to take a deeper look at the algorithm that they have used. 
> 
> The VPRI.org website has been down since Monday and the only reference I could find is a cached version of
the STEPS Toward The Reinvention of Programming,
> 2009 Progress Report Submitted to the National Science Foundation (NSF) October 2009 through Google <https://docs.google.com/viewer?a=v&q=cache:oiduCS-BeDIJ:www.vpri.org/pdf/tr2009016_steps09.pdf+viewpoints+research+successor+predecessor&hl=en&gl=us&pid=bl&srcid=ADGEEShD1B0xdX2kw4-oEhaVrKJei9ALA4pK22zXOLs_iMqc0I3iO4YNVilUbGgKdqvcHTyrZ65waM6WzXTzKdMpnSsoLpJhNBL3cyEx2JDfF3RORgSmkiEkmLkn53AtJxtW8R3nYZB_&sig=AHIEtbSIdvnM808Mw4F9a6ildEZmkHHFIg&pli=1>
> 
> Could anyone provide more pointers about the text layout engine? In particular, is there an image with the
implementation that I might be able to take a deeper look at? Has there been any future work on it that I can
read more about?
> 
> Thanks!
> 
> --
> Nick
> 
> _______________________________________________
(Continue reading)

nchen.dev | 1 Sep 03:49 2011
Picon

Re: More information about the "text layout engine for paragraphs" in VPRI Tech Report

vpri.org just came back up a few hours ago.

I was talking about "Text Field Spec for LObjects" at
<http://www.vpri.org/vp_wiki/index.php/Main_Page>. I found the old image with the prototype and
have been able to download it and play with it. Ted Kaehler has also been kind enough to answer some
questions that I have on it.

Thanks!

--
Nick

On Aug 31, 2011, at 8:42 PM, Julian Leviston wrote:

> vpri.og is working for me.
> 
> Are you talking about Gezira/Nile?
> 
> http://www.vpri.org/vp_wiki/index.php/Gezira
> 
> Julian

Mónica Pinto | 1 Sep 16:24 2011
Picon

MODULARITY: aosd.2012 - Call for Papers -- Research Results -- 3rd and last submission round

*** AOSD 2012 ***

March 25-30, 2012
Hasso-Plattner-Institut Potsdam, Germany
http://aosd.net/2012/

Call for Papers -- Research Results

Modularity transcending traditional abstraction boundaries is
essential for developing complex modern systems - particularly
software and software-intensive systems. Aspect-oriented and other new
forms of modularity and abstraction are attracting a great deal
attention across many domains within and beyond computer science. As
the premier international conference on modularity, AOSD continues to
advance our knowledge and understanding of separation of concerns,
modularity, and abstraction in the broadest senses of these terms.

The 2012 AOSD conference will comprise two main events: "Research
Results" and "Modularity Visions". Both events invite full, scholarly
papers of the highest quality on new ideas and results in areas that
include but are not limited to complex systems, software design and
engineering, programming languages, cyber-physical systems, and other
areas across the whole system life cycle.

Research Results papers are expected to contribute significant new
research results with rigorous and substantial validation of specific
technical claims based on scientifically sound reflections on
experience, analysis, or experimentation.

Modularity Visions papers (solicited in a separate call) are expected
(Continue reading)

John Zabroski | 1 Sep 19:31 2011
Picon

Re: Re: Ceres and Oberon

Has [1] been mentioned yet?  If so, apologies.

I think many here are implicitly referencing this when bringing up Oberon.

[1] http://c2.com/cgi/wiki?HeInventedTheTerm

On Wed, Aug 31, 2011 at 2:25 PM, Alan Kay <alan.nemo <at> yahoo.com> wrote:
The Flex Machine was "the omelet you have to throw away to clean the pan", so I haven't put any effort into saving that history. But there were "4 or 5" pretty good things and "4 or 5" really bad things that helped the Alto-Smalltalk effort a few years later. I'd say that the huge factors after having tried to do one of these were two geniuses: Chuck Thacker (who was an infinitely better hardware designer and builder than I was), and Dan Ingalls (who was infinitely better at most phases of software design and implementation than I was).

Cheers,

Alan

From: Jecel Assumpcao Jr. <jecel-/J8iz1DznIp8UrSeD/g0lQ@public.gmane.org>
To: Alan Kay <alan.nemo-/E1597aS9LQAvxtiuMwx3w@public.gmane.org>; Fundamentals of New Computing <fonc-uVco7kAcSAQ@public.gmane.org>
Sent: Wednesday, August 31, 2011 3:09 PM
Subject: Re: [fonc] Re: Ceres and Oberon

Alan,

thanks for the detailed history!

> 1966 was the year I entered grad school (having programmed for 4-5 years,
> but essentially knowing nothing about computer science). Shortly after
> encounters with and lightning bolts from the sky induced by Sketchpad and
> Simula, I found the Euler papers and thought you could make something with
> "objects" that would be nicer if you used Euler for a basis rather than how
> Simula was built on Algol. That turned out to be the case and I built this into
> the table-top plus display plus pointing device personal computer Ed Cheadle
> and I made over the next few years.

Is this available anywhere beyond the small fragments at

http://www.mprove.de/diplom/gui/kay68.html

and

http://www.mprove.de/diplom/gui/kay69.html

?

Though you often mention the machine itself, I have never seen you put
these texts in the list of what people should read like you do with
Ivan's thesis.

> The last time I looked at Oberon (at Apple more than 15 years ago) it did
> not impress, and did not resemble anything I would call an object-oriented
> language -- or an advance on anything that was already done in the 70s.
> But that's just my opinion. And perhaps it has improved since then.

It was an attempt to step back from the complexity of Modula-2, which is
a good thing. It has the FONC goal of being small enough to be
completely read and understood by one person (he does mention that this
is in the form of a 600 page book in the talk).

In the early 1990s I was trying to build a really low cost computer
around the Self language and a professor who always had interesting
insights suggested that something done with Oberon would require fewer
hardware resources. I studied the language and saw that they had
recently made it object oriented:

http://en.wikipedia.org/wiki/Oberon-2_%28programming_language%29

But it turned out that this was a dead end and the then current system
was built with the original, non object oriented version of the language
(as it is to this day - the OO programming Wirth mentioned in the talk
is the kind of thing you can do in plain C). I liked the size of the
system, but the ALL CAPS code hurt my eyes and the user interface was
awkward (both demonstrators in the movie had problems using it, though
Wirth had the excuse that he hadn't used it in a long time).

-- Jecel




_______________________________________________
fonc mailing list
fonc-uVco7kAcSAQ@public.gmane.org
http://vpri.org/mailman/listinfo/fonc


<div>
<p>Has [1] been mentioned yet?&nbsp; If so, apologies.<br><br>I think many here are implicitly referencing this when bringing up Oberon.<br><br>[1] <a href="http://c2.com/cgi/wiki?HeInventedTheTerm">http://c2.com/cgi/wiki?HeInventedTheTerm</a><br><br></p>
<div class="gmail_quote">On Wed, Aug 31, 2011 at 2:25 PM, Alan Kay <span dir="ltr">&lt;<a href="mailto:alan.nemo@...">alan.nemo <at> yahoo.com</a>&gt;</span> wrote:<br><blockquote class="gmail_quote">
<div><div>
<div><span>The Flex Machine was "the omelet you have to throw away to clean the pan", so I haven't put any effort into saving that history. But there were "4 or 5" pretty good things and "4 or 5" really bad things that helped the Alto-Smalltalk effort a few years later. I'd say that the huge factors after having tried to do one of these were two geniuses: Chuck Thacker (who was an infinitely better hardware designer and builder than I was), and Dan Ingalls (who was infinitely better at most phases of software design and implementation than I was).</span></div>
<div>
<br><span></span>
</div>
<div><span>Cheers,</span></div>
<div>
<br><span></span>
</div>
<div><span>Alan<br></span></div>
<div>
<br><blockquote><div>
<div>
<span>From:</span> Jecel Assumpcao Jr. &lt;<a href="mailto:jecel@..." target="_blank">jecel@...</a>&gt;<br><span>To:</span> Alan Kay &lt;<a href="mailto:alan.nemo@..." target="_blank">alan.nemo@...</a>&gt;; Fundamentals of New Computing &lt;<a href="mailto:fonc@..." target="_blank">fonc@...</a>&gt;<br><span>Sent:</span> Wednesday, August 31, 2011 3:09 PM<br><span>Subject:</span> Re: [fonc] Re: Ceres and Oberon<br><div class="im">
<br>Alan,<br><br>thanks for the detailed history!<br><br>
</div>
<div class="im">&gt; 1966 was the year I entered grad school (having programmed for 4-5 years,<br>&gt; but essentially knowing nothing about computer science). Shortly after<br>&gt; encounters with and lightning bolts from the sky induced by Sketchpad and<br>
&gt; Simula, I found the Euler papers and thought you could make
 something with<br>&gt; "objects" that would be nicer if you used Euler for a basis rather than how<br>&gt; Simula was built on Algol. That turned out to be the case and I built this into<br>&gt; the table-top plus display plus pointing device personal computer Ed Cheadle<br>
&gt; and I made over the next few years. <br><br>
</div>
<div class="im">Is this available anywhere beyond the small fragments at<br><br><a href="http://www.mprove.de/diplom/gui/kay68.html" target="_blank">http://www.mprove.de/diplom/gui/kay68.html</a><br><br>and<br><br><a href="http://www.mprove.de/diplom/gui/kay69.html" target="_blank">http://www.mprove.de/diplom/gui/kay69.html</a><br><br>?<br><br>Though you often mention the machine itself, I have never seen you put<br>
these texts in the list of what people should read like you do with<br>Ivan's thesis.<br><br>
</div>
<div class="im">&gt; The last time I looked at Oberon (at Apple more than 15 years ago) it did<br>&gt; not impress, and did not resemble anything I would call an
 object-oriented<br>&gt; language -- or an advance on anything that was already done in the 70s.<br>&gt; But that's just my opinion. And perhaps it has improved since then.<br><br>
</div>
<div class="im">It was an attempt to step back from the complexity of Modula-2, which is<br>
a good thing. It has the FONC goal of being small enough to be<br>completely read and understood by one person (he does mention that this<br>is in the form of a 600 page book in the talk).<br><br>In the early 1990s I was trying to build a really low cost computer<br>
around the Self language and a professor who always had interesting<br>insights suggested that something done with Oberon would require fewer<br>hardware resources. I studied the language and saw that they had<br>recently made it object oriented:<br><br><a href="http://en.wikipedia.org/wiki/Oberon-2_%28programming_language%29" target="_blank">http://en.wikipedia.org/wiki/Oberon-2_%28programming_language%29</a><br><br>But it turned out that
 this was a dead end and the then current system<br>was built with the original, non object oriented version of the language<br>(as it is to this day - the OO programming Wirth mentioned in the talk<br>is the kind of thing you can do in plain C). I liked the size of the<br>
system, but the ALL CAPS code hurt my eyes and the user interface was<br>awkward (both demonstrators in the movie had problems using it, though<br>Wirth had the excuse that he hadn't used it in a long time).<br><br>-- Jecel<br><br><br><br>
</div>
</div>
</div></blockquote>
</div>
</div></div>
<br>_______________________________________________<br>
fonc mailing list<br><a href="mailto:fonc@...">fonc@...</a><br><a href="http://vpri.org/mailman/listinfo/fonc" target="_blank">http://vpri.org/mailman/listinfo/fonc</a><br><br>
</blockquote>
</div>
<br>
</div>
Alan Kay | 1 Sep 20:04 2011
Picon

Re: Re: Ceres and Oberon

I'm so glad I never read this before (and am looking for ways to forget that I just did ....)

Cheers,

Alan

From: John Zabroski <johnzabroski-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
To: Alan Kay <alan.nemo-/E1597aS9LQAvxtiuMwx3w@public.gmane.org>; Fundamentals of New Computing <fonc-uVco7kAcSAQ@public.gmane.org>
Cc: Jecel Assumpcao Jr. <jecel-/J8iz1DznIp8UrSeD/g0lQ@public.gmane.org>
Sent: Thursday, September 1, 2011 10:31 AM
Subject: Re: [fonc] Re: Ceres and Oberon

Has [1] been mentioned yet?  If so, apologies.

I think many here are implicitly referencing this when bringing up Oberon.

[1] http://c2.com/cgi/wiki?HeInventedTheTerm

On Wed, Aug 31, 2011 at 2:25 PM, Alan Kay <alan.nemo-/E1597aS9LQAvxtiuMwx3w@public.gmane.org> wrote:
The Flex Machine was "the omelet you have to throw away to clean the pan", so I haven't put any effort into saving that history. But there were "4 or 5" pretty good things and "4 or 5" really bad things that helped the Alto-Smalltalk effort a few years later. I'd say that the huge factors after having tried to do one of these were two geniuses: Chuck Thacker (who was an infinitely better hardware designer and builder than I was), and Dan Ingalls (who was infinitely better at most phases of software design and implementation than I was).

Cheers,

Alan

From: Jecel Assumpcao Jr. <jecel-/J8iz1DznIp8UrSeD/g0lQ@public.gmane.org>
To: Alan Kay <alan.nemo-/E1597aS9LQAvxtiuMwx3w@public.gmane.org>; Fundamentals of New Computing <fonc-uVco7kAcSAQ@public.gmane.org>
Sent: Wednesday, August 31, 2011 3:09 PM
Subject: Re: [fonc] Re: Ceres and Oberon

Alan,

thanks for the detailed history!

> 1966 was the year I entered grad school (having programmed for 4-5 years,
> but essentially knowing nothing about computer science). Shortly after
> encounters with and lightning bolts from the sky induced by Sketchpad and
> Simula, I found the Euler papers and thought you could make something with
> "objects" that would be nicer if you used Euler for a basis rather than how
> Simula was built on Algol. That turned out to be the case and I built this into
> the table-top plus display plus pointing device personal computer Ed Cheadle
> and I made over the next few years.

Is this available anywhere beyond the small fragments at

http://www.mprove.de/diplom/gui/kay68.html

and

http://www.mprove.de/diplom/gui/kay69.html

?

Though you often mention the machine itself, I have never seen you put
these texts in the list of what people should read like you do with
Ivan's thesis.

> The last time I looked at Oberon (at Apple more than 15 years ago) it did
> not impress, and did not resemble anything I would call an object-oriented
> language -- or an advance on anything that was already done in the 70s.
> But that's just my opinion. And perhaps it has improved since then.

It was an attempt to step back from the complexity of Modula-2, which is
a good thing. It has the FONC goal of being small enough to be
completely read and understood by one person (he does mention that this
is in the form of a 600 page book in the talk).

In the early 1990s I was trying to build a really low cost computer
around the Self language and a professor who always had interesting
insights suggested that something done with Oberon would require fewer
hardware resources. I studied the language and saw that they had
recently made it object oriented:

http://en.wikipedia.org/wiki/Oberon-2_%28programming_language%29

But it turned out that this was a dead end and the then current system
was built with the original, non object oriented version of the language
(as it is to this day - the OO programming Wirth mentioned in the talk
is the kind of thing you can do in plain C). I liked the size of the
system, but the ALL CAPS code hurt my eyes and the user interface was
awkward (both demonstrators in the movie had problems using it, though
Wirth had the excuse that he hadn't used it in a long time).

-- Jecel




_______________________________________________
fonc mailing list
fonc <at> vpri.org
http://vpri.org/mailman/listinfo/fonc




<div><div>
<div><span>I'm so glad I never read this before (and am looking for ways to forget that I just did ....)</span></div>
<div>
<br><span></span>
</div>
<div><span>Cheers,</span></div>
<div>
<br><span></span>
</div>
<div><span>Alan<br></span></div>
<div>
<br><blockquote><div><div>
<span>From:</span> John Zabroski &lt;johnzabroski@...&gt;<br><span>To:</span> Alan Kay &lt;alan.nemo@...&gt;; Fundamentals of New Computing &lt;fonc@...&gt;<br><span>Cc:</span> Jecel Assumpcao Jr. &lt;jecel@...&gt;<br><span>Sent:</span> Thursday, September 1, 2011 10:31 AM<br><span>Subject:</span> Re: [fonc] Re: Ceres and Oberon<br><br><div>Has [1] been mentioned yet?&nbsp; If so, apologies.<br><br>I think many here are implicitly referencing this when bringing up Oberon.<br><br>[1] <a rel="nofollow" target="_blank" href="http://c2.com/cgi/wiki?HeInventedTheTerm">http://c2.com/cgi/wiki?HeInventedTheTerm</a><br><br><div class="yiv1323576762gmail_quote">On Wed, Aug 31, 2011 at 2:25 PM, Alan Kay <span dir="ltr">&lt;<a rel="nofollow" ymailto="mailto:alan.nemo@..." target="_blank" href="mailto:alan.nemo@...">alan.nemo@...</a>&gt;</span> wrote:<br><blockquote class="yiv1323576762gmail_quote">
<div><div>
<div><span>The Flex Machine was "the omelet you have to throw away to clean the pan", so I haven't put any effort into saving that history. But there were "4 or 5" pretty good things and "4 or 5" really bad things that helped the Alto-Smalltalk effort a few years later. I'd say that the huge factors after having tried to do one of these were two geniuses: Chuck Thacker (who was an infinitely better hardware designer and builder than I was), and Dan Ingalls (who was infinitely better at most phases of software design and implementation than I was).</span></div>
<div>
<br><span></span>
</div>
<div><span>Cheers,</span></div>
<div>
<br><span></span>
</div>
<div><span>Alan<br></span></div>
<div>
<br><blockquote><div>
<div>
<span>From:</span> Jecel Assumpcao Jr. &lt;<a rel="nofollow" ymailto="mailto:jecel@..." target="_blank" href="mailto:jecel@...">jecel@...</a>&gt;<br><span>To:</span> Alan Kay &lt;<a rel="nofollow" ymailto="mailto:alan.nemo@..." target="_blank" href="mailto:alan.nemo@...">alan.nemo@...</a>&gt;; Fundamentals of New Computing &lt;<a rel="nofollow" ymailto="mailto:fonc@..." target="_blank" href="mailto:fonc@...">fonc@...</a>&gt;<br><span>Sent:</span> Wednesday, August 31, 2011 3:09 PM<br><span>Subject:</span> Re: [fonc] Re: Ceres and Oberon<br><div class="yiv1323576762im">
<br>Alan,<br><br>thanks for the detailed history!<br><br>
</div>
<div class="yiv1323576762im">&gt; 1966 was the year I entered grad school (having programmed for 4-5 years,<br>&gt; but essentially knowing nothing about computer science). Shortly after<br>&gt; encounters with and lightning bolts from the sky induced by Sketchpad and<br>
&gt; Simula, I found the Euler papers and thought you could make
 something with<br>&gt; "objects" that would be nicer if you used Euler for a basis rather than how<br>&gt; Simula was built on Algol. That turned out to be the case and I built this into<br>&gt; the table-top plus display plus pointing device personal computer Ed Cheadle<br>
&gt; and I made over the next few years. <br><br>
</div>
<div class="yiv1323576762im">Is this available anywhere beyond the small fragments at<br><br><a rel="nofollow" target="_blank" href="http://www.mprove.de/diplom/gui/kay68.html">http://www.mprove.de/diplom/gui/kay68.html</a><br><br>and<br><br><a rel="nofollow" target="_blank" href="http://www.mprove.de/diplom/gui/kay69.html">http://www.mprove.de/diplom/gui/kay69.html</a><br><br>?<br><br>Though you often mention the machine itself, I have never seen you put<br>
these texts in the list of what people should read like you do with<br>Ivan's thesis.<br><br>
</div>
<div class="yiv1323576762im">&gt; The last time I looked at Oberon (at Apple more than 15 years ago) it did<br>&gt; not impress, and did not resemble anything I would call an
 object-oriented<br>&gt; language -- or an advance on anything that was already done in the 70s.<br>&gt; But that's just my opinion. And perhaps it has improved since then.<br><br>
</div>
<div class="yiv1323576762im">It was an attempt to step back from the complexity of Modula-2, which is<br>
a good thing. It has the FONC goal of being small enough to be<br>completely read and understood by one person (he does mention that this<br>is in the form of a 600 page book in the talk).<br><br>In the early 1990s I was trying to build a really low cost computer<br>
around the Self language and a professor who always had interesting<br>insights suggested that something done with Oberon would require fewer<br>hardware resources. I studied the language and saw that they had<br>recently made it object oriented:<br><br><a rel="nofollow" target="_blank" href="http://en.wikipedia.org/wiki/Oberon-2_%28programming_language%29">http://en.wikipedia.org/wiki/Oberon-2_%28programming_language%29</a><br><br>But it turned out that
 this was a dead end and the then current system<br>was built with the original, non object oriented version of the language<br>(as it is to this day - the OO programming Wirth mentioned in the talk<br>is the kind of thing you can do in plain C). I liked the size of the<br>
system, but the ALL CAPS code hurt my eyes and the user interface was<br>awkward (both demonstrators in the movie had problems using it, though<br>Wirth had the excuse that he hadn't used it in a long time).<br><br>-- Jecel<br><br><br><br>
</div>
</div>
</div></blockquote>
</div>
</div></div>
<br>_______________________________________________<br>
fonc mailing list<br><a rel="nofollow" ymailto="mailto:fonc@..." target="_blank" href="mailto:fonc@...">fonc <at> vpri.org</a><br><a rel="nofollow" target="_blank" href="http://vpri.org/mailman/listinfo/fonc">http://vpri.org/mailman/listinfo/fonc</a><br><br>
</blockquote>
</div>
<br>
</div>
<br><br>
</div></div></blockquote>
</div>
</div></div>
Jecel Assumpcao Jr. | 1 Sep 05:00 2011

a little more FLEXibility (was: Re: Ceres and Oberon)

Alan,

> The Flex Machine was "the omelet you have to throw away to clean the pan",
> so I haven't put any effort into saving that history.

Fair enough! Having the table of contents but not the text made me think
that perhaps the section B.6.b.ii The Disk as a Serial "Associative
Memory" and B.6.c. An Associativeley Mapped LSI Memory might be
interesting in light of Ian's latest paper. Or the first part might be
more related to OOZE instead.

> But there were "4 or 5" pretty good things and "4 or 5" really bad things that
> helped the Alto-Smalltalk effort a few years later.

Was being able to input drawings one of the good things? There was one
Lisp GUI that put a lot of effort into allowing you to input objects
instead of just text. It did that by outputting text but keeping track
of where it came from. So if you pointed to the text generated by
listing the contents of a disk directory while there was some program
waiting for input, that program would read the actual entry object.

It is frustrating for me that while the Squeak VM could easily handle an
expression like

myView add: <yellowEllipseMorph> copy.

I have no way of typing that. I can't use any object as a literal nor as
input. In Etoys I can get close enough by getting  a tile representing
the yellowEllpiseMorph from its halo and use that in expressions. In
Self I could add a constant slot with some easy to type value, like 0,
and then drag the arrow from that slot to point to the object I really
wanted. It was a bit indirect but it worked and I used this a lot. The
nice thing about having something like this is that you never need
global variable again.

> I'd say that the huge factors after having tried to do one of these were two
> geniuses: Chuck Thacker (who was an infinitely better hardware designer and
> builder than I was), and Dan Ingalls (who was infinitely better at most phases
> of software design and implementation than I was).

True. You were lucky to have them, though perhaps we might say Bob
Taylor had built that luck into PARC.

-- Jecel

Bert Freudenberg | 1 Sep 22:22 2011
Picon

Re: a little more FLEXibility (was: Re: Ceres and Oberon)

On 01.09.2011, at 15:17, Jecel Assumpcao Jr. wrote:
> Was being able to input drawings one of the good things? There was one
> Lisp GUI that put a lot of effort into allowing you to input objects
> instead of just text. It did that by outputting text but keeping track
> of where it came from. So if you pointed to the text generated by
> listing the contents of a disk directory while there was some program
> waiting for input, that program would read the actual entry object.
> 
> It is frustrating for me that while the Squeak VM could easily handle an
> expression like
> 
> myView add: <yellowEllipseMorph> copy.
> 
> I have no way of typing that. I can't use any object as a literal nor as
> input. In Etoys I can get close enough by getting  a tile representing
> the yellowEllpiseMorph from its halo and use that in expressions. In
> Self I could add a constant slot with some easy to type value, like 0,
> and then drag the arrow from that slot to point to the object I really
> wanted. It was a bit indirect but it worked and I used this a lot. The
> nice thing about having something like this is that you never need
> global variable again.

In a Squeak workspace you can enable the "create textual references to dropped morphs" checkbox which at
least lets you do this interactively. Saving as project and loading keeps this working.

However, outside of the Etoys environment hardly anyone in the Squeak community uses projects - all
exchange is based on text files. While the system itself is nicely object-based, its boundaries are
dumbed down to a manageable level. Lots of tools exist to deal with text, but storing, sharing, or merging
objects is still hard. Perhaps because in Smalltalk objects are still too tightly bound to their
environment? 

- Bert -

John Zabroski | 1 Sep 22:49 2011
Picon

Good books on control theory?

Folks,

Lately I've been learning about control theory from research papers.  I started off with the classical Witsenhausen counterexample paper, and have been reading a lot of papers about just that counterexample.  I'm really interested in control theory problems that overlap with information theory, which is just the sort of problem Witsenhausen focused upon.

I'm also wondering if any computer scientists have applied control theory to any computational problems.  I'm a little stunned that I can't find anything relating things like the Actor Model to ideas from control theory.

Just thinking out loud, but also welcoming suggestions!

Cheers,
Z-Bo

<div><p>Folks,<br><br>Lately I've been learning about control theory from research papers.&nbsp; I started off with the classical Witsenhausen counterexample paper, and have been reading a lot of papers about just that counterexample.&nbsp; I'm really interested in control theory problems that overlap with information theory, which is just the sort of problem Witsenhausen focused upon.<br><br>I'm also wondering if any computer scientists have applied control theory to any computational problems.&nbsp; I'm a little stunned that I can't find anything relating things like the Actor Model to ideas from control theory.<br><br>Just thinking out loud, but also welcoming suggestions!<br><br>Cheers,<br>Z-Bo<br></p></div>
Ken G. Brown | 1 Sep 23:03 2011
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Re: Good books on control theory?

Try Googling state space analysis of control systems.
Maybe that will result in some leads.

Ken

At 4:49 PM -0400 9/1/11, John Zabroski apparently wrote:
>Folks,
>
>Lately I've been learning about control theory from research papers.  I started off with the classical
Witsenhausen counterexample paper, and have been reading a lot of papers about just that
counterexample.  I'm really interested in control theory problems that overlap with information
theory, which is just the sort of problem Witsenhausen focused upon.
>
>I'm also wondering if any computer scientists have applied control theory to any computational
problems.  I'm a little stunned that I can't find anything relating things like the Actor Model to ideas
from control theory.
>
>Just thinking out loud, but also welcoming suggestions!
>
>Cheers,
>Z-Bo
>
>_______________________________________________
>fonc mailing list
>fonc@...
>http://vpri.org/mailman/listinfo/fonc

Max OrHai | 2 Sep 00:32 2011
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Re: Good books on control theory?

My "thinking out loud" response would be that classical control theory may not be very well suited to CS-type problems, which often can't even be approximated by linear systems. Cybernetic feedback control, a la Weiner, is IIRC mostly about systems with a few continuous variables, while our problems more often involve large numbers of discrete variables. But, there's certainly quite a bit more to control theory than I'm aware of.


Wolfram MathWorld recommends Zabczyk:

There are plenty of other, smaller, less comprehensive intro texts out there too... sorry I can't recommend one first-hand.

-- Max



On Thu, Sep 1, 2011 at 1:49 PM, John Zabroski <johnzabroski-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
Folks,

Lately I've been learning about control theory from research papers.  I started off with the classical Witsenhausen counterexample paper, and have been reading a lot of papers about just that counterexample.  I'm really interested in control theory problems that overlap with information theory, which is just the sort of problem Witsenhausen focused upon.

I'm also wondering if any computer scientists have applied control theory to any computational problems.  I'm a little stunned that I can't find anything relating things like the Actor Model to ideas from control theory.

Just thinking out loud, but also welcoming suggestions!

Cheers,
Z-Bo

_______________________________________________
fonc mailing list
fonc-uVco7kAcSAQ@public.gmane.org
http://vpri.org/mailman/listinfo/fonc


<div>
<p>My "thinking out loud" response would be that classical control theory may not be very well suited to CS-type problems, which often can't even be approximated by linear systems. Cybernetic feedback control, a la Weiner, is IIRC mostly about systems with a few continuous variables, while our problems more often involve large numbers of discrete variables. But, there's certainly quite a bit more to control theory than I'm aware of.</p>
<div>
<br>
</div>
<div>Wolfram MathWorld recommends Zabczyk:<div><a href="http://www.amazon.com/exec/obidos/ASIN/0817636455">http://www.amazon.com/exec/obidos/ASIN/0817636455</a></div>
<div><br></div>
<div>There are plenty of other, smaller, less comprehensive intro texts out there too... sorry I can't recommend one first-hand.</div>
<div><br></div>
<div>-- Max</div>
<div><br></div>
<div>
<br><br><div class="gmail_quote">On Thu, Sep 1, 2011 at 1:49 PM, John Zabroski <span dir="ltr">&lt;<a href="mailto:johnzabroski@...">johnzabroski@...</a>&gt;</span> wrote:<br><blockquote class="gmail_quote">Folks,<br><br>Lately I've been learning about control theory from research papers.&nbsp; I started off with the classical Witsenhausen counterexample paper, and have been reading a lot of papers about just that counterexample.&nbsp; I'm really interested in control theory problems that overlap with information theory, which is just the sort of problem Witsenhausen focused upon.<br><br>I'm also wondering if any computer scientists have applied control theory to any computational problems.&nbsp; I'm a little stunned that I can't find anything relating things like the Actor Model to ideas from control theory.<br><br>Just thinking out loud, but also welcoming suggestions!<br><br>Cheers,<br>Z-Bo<br><br>_______________________________________________<br>
fonc mailing list<br><a href="mailto:fonc@...">fonc@...</a><br><a href="http://vpri.org/mailman/listinfo/fonc" target="_blank">http://vpri.org/mailman/listinfo/fonc</a><br><br>
</blockquote>
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