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From: Taral <taraloza_at_gmail.com>
Date: Wed, 7 Sep 2005 04:23:46 -0700

Thanks a lot guys for your prompt response. Both, yours and Kristoffer's
responses were very helpful indeed. Pretty soon I will try to write a small
package to do the ORM (Object Relation Management). The examples you
provided will be extremely useful in this case. Just to give you some idea,
I'm thinking along this design:

Class Relationship -parameter FromClass ToClass RelationshipNumber
isConditional isMultiple identifiersList

Of course, I chose descriptive names here. Specially isConditional flag is
used to differentiate 1:0..1 and 1:0..n from 1:1 and 1:1..n types.

Well, I will be in touch with you guys on further development on my side.

By the way, I can not resist myself asking you guys about testing done for
XOTcl. I'm planning to use it for implantable Medical Device hard-real time
firmware system where bugs are not allowed at all. Reading you note about
the bug in expr method, do you mind giving me a small update on what type of
testing is done on this library and how much stable is it from your
experience?

Are there any plans to provide more of object relation management
functionality in the library itself? When are you planning the next release?

I was wondering about whom I'm talking to. You guys are obviously from
Germany/Austria based on my guess from your email address. It would be nice
to know you guys little more to help the communication. Do you guys have any
personal webpage? I don't have one myself :( But now I feel like I should
have one. So I will try to put up one sometime soon.

Thanks again,
Taral


On 9/5/05, Gustaf Neumann <neumann_at_wu-wien.ac.at> wrote:
>
> Taral schrieb:
>
> > Hello,
> >
> > I recently came across XOTcl and found it very very useful. I am
> > working on optimizing some legacy compiler code which is written in
> > TCL. I would like to make it object-oritented and so I started using
> > XOTcl. So far I have found aouut 90% reduction in execution time.
> > Overall I'm getting great performance by using XOTcl.
>
> wow, this is an impressive number; good to hear that.
>
> > I would like to Thank You guys for writing such a great library.
> >
> > Of course I have couple of questions for you. I will really appreciate
> > it if you can help me here.
> >
> > (1) Is there any way to all the objects or instances based on
> > parameter value? For example, I would like to request object names of
> > all objects where given parameter's value is equal to 5.
>
> There is no built-in support for this. a straigthforward approach is the
> following which might
> be sufficient in many situations:
>
> ===========
> # define method expr for all Objects, the operands are taken from
> # the instance variables
> Object instforward expr -objscope
>
> # define method select with some abitrary tcl expression. All objects,
> # for which the expression returns 1 are returned
> Class instproc select {expr} {
> set result_list [list]
> foreach o [my allinstances] {
> if {![catch {$o expr $expr} result]} {
> puts "$o expr {$expr} -> $result"
> if {$result} {
> lappend result_list $o
> }
> }
> }
> return $result_list
> }
> ===========
>
> so, now we define a view classes and objects with some instance variables
>
> Class C -parameter {{x 10}}
> Class D -superclass C
>
> C c1
> C c2 -x 11
> D d1 -x 100
> D d2
> D d3
> d3 unset x
>
> finally, we try it out with some demo queries
>
> foreach q {
> {$x > 10}
> {$x >= 10}
> {$x < 1}
> {[string match *00* $x]}
> } {
> puts "C select $q --> {[lsort [C select $q]]}\n"
> }
>
> Note that in this example, all instances of C are checked for the
> expression, if
> you use "... [Object select {$x > 10}]", all objects will be checked.
>
> This approach might be good enough for small examples and medium
> speed requirements. If you have larger number of objects, and you cant
> restrict the query to smaller classes, you should try to build an index
> based on associative arrays, which could replace the "allinstances"
> in the code above.
>
> > (2) Do you have more example code pieces? I would like to see more
> > sample implementation to help me with the syntax. I'm also learning
> > TCL language at the same time using XOTcl :)
>
> i am sure, you have seen the tutorial and the examples in xotcl*/apps
> and xotcl*/library. There are a few more on:
>
> http://mini.net/tcl/XOTcl
> http://wiki.tcl.tk/references/10971!
>
> > (3) Is there any way to represent relationship across two classes? For
> > example, Class A is related to Class B with one-to-many relationship.
>
> a few class/class relations and object/class relations are maintained
> by xotcl (e.g. superclass,
> class, mixins). A start point might be ::xotcl::Relations, which is
> used to implement a
> uniform interface to mixins (and instmixins ...), which allows to
> specify "... mixin add ...", #
> "... mixin delete ...", "... mixin set ...", etc. In principle, the
> same interface could be used
> for application level relations as well...
>
> In current applications, the classes use and maintain a list of related
> object/classes.
> Often, it is conveniant to use aggregations to express 1:1 or 1:n
> relationships.
>
> > (4) If there is a way to define relationship, is it possible to query
> > objects of classes in the relationship? For example, I would like to
> > get all the objects of Class B related to given object of Class A
> > (like a1) across given one-to-many relationship. In this case result
> > would be list of object handles of Class B that matches based on given
> > primary key (identifier) value between class A and B.
>
> a good key identifier is the object name. see the following snipplet,
> how such behavior
> could be obtained. We define class A, which maintains the relationship
> to some other
> objects. if an instances exists that relates e.g. to object c1, we could
> check there some
> properties with expr like above...
>
> Class A -parameter {relates_to}
>
> A a1
> A a2
>
> a1 set relates_to {c1 c2}
>
> foreach o [A allinstances] {
> catch {
> if {[lsearch -exact [$o relates_to] c2] > -1} {
> puts "could check $o"
> }
> }
> }
>
> hope theses examples help a little.
>
> -gustaf
>
> PS: when i was writing this mail i saw that the classtack information
> within methods called via the method "expr" is not correct. It will
> be fixed in the next release....
>
> >
> > Please provide some guidance to implement above functionality using
> XOTcl.
> >
> > Thanks a lot in advance.
> >
> > May be in future I would like to contribute to XOTcl. I wish to be in
> > touch with you guys.
> >
> > Regards,
> > Taral
>
>
>

From: Zoran Vasiljevic <zoran_at_archiware.com>
Date: Wed, 8 Jan 2003 15:46:24 +0100

On Wednesday 08 January 2003 16:37, Adrian Wallaschek wrote:
> Hi there!
>
> I do like version numbers, but there is a "too much" in everything.
>

The x.y.z is perfectly well adopted by the OS community.
In particular, most of the OS packages follow this
major.minor.patch versioning scheme, right?


> What is the deeper benefit of having the version number for xotcl
> recursively even inside the source-tree?

I see none, must admit.


> When running xotcl-1.0.1/xotclsh I do find ..../xotcl-1.0 in the auto_path
> instead of the required/expected .../xotcl-1.0.1.

This is, indeed, a problem which should be fixed.

Cheers,
Zoran

From: Scott Gargash <scottg_at_atc.creative.com>
Date: Tue, 14 Mar 2006 20:51:07 -0700

Hello,

I'm trying to make a pool of managed resources. At the start-of-day, the pool is filled with a
number of object instances. A client can retrieve an object instance from the pool, and I have a
mixin class that overides destroy to automatically returns the instance to the pool upon
destruction.

The objects are all initially created as children of the pool, and it was my intent to have an
acquiring object take ownership of the instance by move'ing the instance into itself. However, it
seems that move'ing an object invokes the destroy method, which then triggers my mixin and returns
it to the pool.

It seems that move shouldn't destroy the object, as it's only renaming it. Is this the intended
behavior? Would anything bad happen if, instead of move'ing the instance, I were to use Tcl's rename
command to move the object? Is there a better way to get where I'm trying to go?

      Scott

BTW, I notice there's not much activity on this mailing list. XOTcl's object model is sufficiently
new to me that I've got lots of questions on the "right" way to do things, but I hate to be filling
up everyone's mailbox. Is there a more appropriate place to be asking questions?


Notice
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From: Andreas Kupries <andreask_at_activestate.com>
Date: Tue, 09 Apr 2013 13:24:39 -0700

[[ Notes:

   Karl Lehenbauer of FlightAware is confirmed as our Keynote speaker.
   http://www.flightaware.com

]]

20'th Annual Tcl/Tk Conference (Tcl'2013)
http://www.tcl.tk/community/tcl2013/

September 23 - 27, 2013
Bourbon Orleans Hotel
New Orleans, Louisiana, USA
http://www.bourbonorleans.com/

Important Dates:

Abstracts and proposals due June 22, 2013
Notification to authors August 5, 2013
Author materials due September 2, 2013
Tutorials Start September 23, 2013
Conference starts September 25, 2013

Email Contact: tclconference_at_googlegroups.com

Submission of Summaries

Tcl/Tk 2013 will be held in New Orleans, Louisiana, USA from September
23 - 27, 2013. The program committee is asking for papers and
presentation proposals from anyone using or developing with Tcl/Tk
(and extensions). Past conferences have seen submissions covering a
wide variety of topics including:

* Scientific and engineering applications
* Industrial controls
* Distributed applications and Network Managment
* Object oriented extensions to Tcl/Tk
* New widgets for Tk
* Simulation and application steering with Tcl/Tk
* Tcl/Tk-centric operating environments
* Tcl/Tk on small and embedded devices
* Medical applications and visualization
* Use of different programming paradigms in Tcl/Tk and proposals for new
  directions.
* New areas of exploration for the Tcl/Tk language

Submissions should consist of an abstract of about 100 words and a
summary of not more than two pages, and should be sent as plain text
to <tclconference AT googlegroups DOT com> no later than August 5,
2013. Authors of accepted abstracts will have until September 2, 2013
to submit their final paper for the inclusion in the conference
proceedings. The proceedings will be made available on digital media,
so extra materials such as presentation slides, code examples, code
for extensions etc. are encouraged.

Printed proceedings will be produced as an on-demand book at lulu.com

The authors will have 25 minutes to present their paper at the
conference.

The program committee will review and evaluate papers according to the
following criteria:

* Quantity and quality of novel content
* Relevance and interest to the Tcl/Tk community
* Suitability of content for presentation at the conference

Proposals may report on commercial or non-commercial systems, but
those with only blatant marketing content will not be accepted.

Application and experience papers need to strike a balance between
background on the application domain and the relevance of Tcl/Tk to
the application. Application and experience papers should clearly
explain how the application or experience illustrates a novel use of
Tcl/Tk, and what lessons the Tcl/Tk community can derive from the
application or experience to apply to their own development efforts.

Papers accompanied by non-disclosure agreements will be returned to
the author(s) unread. All submissions are held in the highest
confidentiality prior to publication in the Proceedings, both as a
matter of policy and in accord with the U. S. Copyright Act of 1976.

The primary author for each accepted paper will receive registration
to the Technical Sessions portion of the conference at a reduced rate.

Other Forms of Participation

The program committee also welcomes proposals for panel discussions of
up to 90 minutes. Proposals should include a list of confirmed
panelists, a title and format, and a panel description with position
statements from each panelist. Panels should have no more than four
speakers, including the panel moderator, and should allow time for
substantial interaction with attendees. Panels are not presentations
of related research papers.

Slots for Works-in-Progress (WIP) presentations and Birds-of-a-Feather
sessions (BOFs) are available on a first-come, first-served basis
starting in August 5, 2013. Specific instructions for reserving WIP
and BOF time slots will be provided in the registration information
available in June 3, 2013. Some WIP and BOF time slots will be held open
for on-site reservation. All attendees with an interesting work in
progress should consider reserving a WIP slot.

Registration Information

More information on the conference is available the conference Web
site (http://www.tcl.tk/community/tcl2013/) and will be published on
various Tcl/Tk-related information channels.

To keep in touch with news regarding the conference and Tcl events in
general, subscribe to the tcl-announce list. See:
http://code.activestate.com/lists/tcl-announce to subscribe to the
tcl-announce mailing list.


Conference Committee

Clif Flynt Noumena Corp General Chair, Website Admin
Andreas Kupries ActiveState Software Inc. Program Chair
Gerald Lester KnG Consulting, LLC Site/Facilities Chair
Arjen Markus Deltares
Brian Griffin Mentor Graphics
Cyndy Lilagan Nat. Museum of Health & Medicine, Chicago
Donal Fellows University of Manchester
Jeffrey Hobbs ActiveState Software Inc.
Kevin Kenny GE Global Research Center
Larry Virden
Mike Doyle National Museum of Health & Medicine, Chicago
Ron Fox NSCL/FRIB Michigan State University
Steve Landers Digital Smarties

Contact Information tclconference_at_googlegroups.com


Tcl'2013 would like to thank those who are sponsoring the conference:

ActiveState Software Inc.
Buonacorsi Foundation
Mentor Graphics
Noumena Corp.
SR Technology
Tcl Community Association

From: Jonathan Kelly <jonkelly_at_fastmail.fm>
Date: Fri, 10 Aug 2012 11:39:46 +1000

Hi,

I'm trying to get my head into the "named object" space. I was looking
at the container example for a way in and now I'm stuck (again).

nx::Class create SimpleContainer {
  :property {memberClass ::MyItem}
  :property {prefix member}

  # Require the method "autoname" for generating nice names
  :require method autoname

  # The method new is responsible for creating a child of the current
  # container.
  :public method new {args} {
    set item [${:memberClass} create [:]::[:autoname ${:prefix}]
    {*}$args]
  }
}

What does the ":require method autoname" do?

I think I understand what [:autoname ${:prefix}] is/does but what on
earth is "[:]::[:autoname ${:prefix}]" ?

Jon

From: Kristoffer Lawson <setok_at_fishpool.com>
Date: Sat, 4 Sep 2004 19:54:49 +0300 (EEST)

This could be related to what others have reported but:

[~/svn/codebase/trunk/tcl] package require XOTcl
1.3
[~/svn/codebase/trunk/tcl] namespace import xotcl::*
[~/svn/codebase/trunk/tcl] namespace eval foo {
>Class Foo
>Foo instproc blah {} {puts jou}
>Foo proc bar {} {puts bar}
>}
[~/svn/codebase/trunk/tcl] namespace delete foo
called Tcl_FindHashEntry on deleted table
Abort


                               / http://www.fishpool.com/~setok/

From: Stefan Sobernig <stefan.sobernig_at_wu.ac.at>
Date: Wed, 28 Mar 2012 18:08:43 +0200

René,

> A property can be set at creation time with
> <class> create<object> -property value
> and later get with
> <object> property
> and set with
> <object> property value
>
> What was the reason not to use -property
> as method name of the accessor function?

A straight forward (though not exhaustive) answer is that the dash
prefix ("-") is being used for non-positional parameters in the NX
concrete syntax (object and method parameters). While this is not a
barrier to using the dash as a general prefix to getter/setter names (or
method names in general), it might produce some distortion.

More importantly, yet less visible, dashed arguments to object
dispatches (i.e., Tcl commands representing NX objects) do carry meaning
which might lead to conflicts: A point in case are the special-purpose
"-system" and "-local" arguments which can be used in self-dispatches,
for example:

package req nx::test

Object create o {
   # ! gives a warning !
   :public method -local args {
     return 1
   }

   :private method bar args {
     return 0
   }
   :public method foo {} {
     # ! subtle differences !
     return [:-local bar]-[: -local bar]
   }
}

? {o foo} 1-0

This example will give you a warning (NX checks for dash-prefixed names
at critical places) and demonstrates one of the subtle differences one
runs into when using "-" beyond what is backed into NX (for good
reasons, though).

Along these lines, NX won't allow the following custom-made fix of yours:

Object create o {
   :property {-local 1}
}

-> invalid setter name "-local" (must not start with a dash or colon)

To summarise: While not carved in stone, the "-" (as the colon ":") has
some preserved, internal meaning at some places in NX, in particular for
argument processing.

> The -property notation seems IMO better
> and does not interfere with normal method
> names of an object.

The issue of using dashed or undashed names, however, does not really
address your concern of bloating an object's method interface.

There is a slightly more flexible API available to you for fine-tuning
properties: You may specify properties with/without auto-generated
setter/getter methods AND/OR with/without object parameters (to use a
-<propertyName> in new or create calls), i.e., the use of "variable" and
its "-config" and "-accessor" flags:

Class create C {
   :variable x 1
   :public method X {} {
     return [incr :x -1]
   }
   :variable -config y
   :variable -config -accessor z; # "somewhat" equivalent to ":property z"
}

? {[C create ::c] X} 0; # "C new -x" (object parameter) not available!
? {[C create ::c] info lookup methods x} ""; # "[C new] x"
(accessor/mutator method) not available!
? {[C create ::c -y 2] y} "::c: unable to dispatch method 'y'"; # object
parameter available, accessor method missing
? {[C create ::c -z 3] z} 3; # both in place!

> It is like the option
> notation in tk.

Indeed :)

Right now, there is no ready-made, builtin interface resembling Tk's
options (or fconfigure) in NX. However, it could be easily scripted if
needed.

Let me know if I can provide you further assistance, in whatever direction.

cheers
//stefan





>
>
> Regards,
> rene
> _______________________________________________
> Xotcl mailing list
> Xotcl_at_alice.wu-wien.ac.at
> http://alice.wu-wien.ac.at/mailman/listinfo/xotcl
>

-- 
Institute for Information Systems and New Media
Vienna University of Economics and Business
Augasse 2-6, A-1090 Vienna
`- http://nm.wu.ac.at/en/sobernig
`- stefan.sobernig_at_wu.ac.at
`- ss_at_thinkersfoot.net
`- +43-1-31336-4878 [phone]
`- +43-1-31336-746 [fax]

From: Jeff Hobbs <jeffh_at_ActiveState.com>
Date: Sun, 17 Oct 2004 15:21:33 -0700

> xow - A megawidget framework. This is a package that allows
> xotcl objects to be megawidgets.

Does this handle the option db correctly, do composition
of megawidgets, handle focus and events right, etc.?

> xcentuate - a theme engine for tk. This isn't all that
> important on windows, but on unix tk often needs a little
> help looking good. This package provides a very simple method
> of defining and changing the look of tk apps. It can even do
> it on the fly.

I would not propagate this in favor of Tile. There is
also already the 'style' package in tklib (which again
may be abortive when Tile becomes part of 8.5). What
features does xcentuate really provide? Should they not
just go into 'style'?

> xout - a unit testing framework. I know, I know, tcl already
> provides one, tcltest. But I found tcltest to be too
> cumbersome and clunky. I'd write some tests, but maintaining
> those tests often was neglected because of the amount of
> programming overhead needed to write complex test cases. xout

Did you compare against tcltest v1 or v2?

> I mention all of this because if other have some handy xotcl
> packages, I'd be interested in creating a formal xotcllib
> project. Perhaps something at sourceforge. I'll be making
> these available soon either way.

I think that would be a handy thing as an addon.

  Jeff Hobbs, The Tcl Guy
  http://www.ActiveState.com/, a division of Sophos

From: Andreas Kupries <andreask_at_activestate.com>
Date: Sun, 18 Aug 2013 17:00:39 -0700

Founder of Tool Command Language to talk about Tcl Past, Present &
Future

Ann Arbor, MI -- August 16, 2013 -- The Tcl/Tk User Association, which
is celebrating over 20 years of innovation using the Tool Command
Language (Tcl), confirmed today that John Ousterhout will be a
Featured Speaker at the conference in New Orleans, LA from Sept 23-27,
2013.

 Ousterhout is the original developer of the Tcl and Tk programming
language, a combination of the Tool Command Language and the Tk
graphical user interface tookit (Tk). His presentation will focus on
the evolution of Tcl/Tk from its original language format created at
the University of California Berkeley to the most robust and
easy-to-learn dynamic programming language that seamlessly powers
today's applications. He is also the author of Tcl and the Tk ToolKit
(2nd Edition).

"John started a revolution born out of frustration," says Clif Flynt,
President, Tcl Community Association and author of Tcl/Tk: A
Developer's Guide. "Before Tcl, programmers devised their own
languages that were intended to be embedded into applications. By
creating Tcl/Tk, John created a language for rapid prototyping that
works immediately."

The Tcl New and Proven user conference will feature several Tcl
experts including Jeff Hobbs, Chief Technical Officer at ActiveState,
Gerald Lester, creator of Tcl Web Services and a keynote speech by
Karl Lehenbauer of FlightAware.com. Programmers attending the
conference will learn the best practices for using Tcl's new
object-oriented commands and widgets as well as seeing new
applications and techniques in the fields ranging from business
applications to health, aerospace and beyond.

"The Tcl New & Proven User Conference will be focusing on innovation
throughout the years," says Flynt. "We are very pleased to have two of
the people who helped create the Tcl we know today at our 20th
conference."

Interested in attending the Tcl conference? Go to
http://www.tcl.tk/community/tcl2013/ to register. Learn more about
Tcl/Tk by visiting the Tcl Developer Xchange http://www.tcl.tk/ where
you can download Tcl 8.6 and a free trial of TDK 5 (Tcl Dev Kit).

###

About Tcl/Tk (http://www.tcl.tk/)

Celebrating over 20 years of providing rapid prototyping, Tool Command
Language (Tcl) is an open source, robust, powerful and easy-to-learn
dynamic programming language ideal for today's web and desktop
applications, networking, administration, and testing. Tk is a
graphical user interface toolkit that enables the development of
native-looking GUIs on multiple platforms such as Windows, Mac OS X
and Linux. The combination of Tcl and the Tk GUI toolkit is referred
to as Tcl/Tk..
 
The vibrant Tcl user community comes together on the Tcl Developer
Xchange website hosted by ActiveState (http://www.tcl.tk/), which
provides a variety of resources for programmers working with Tcl/Tk to
increase their productivity and share ideas. Worldwide Tcl
conferences, Tcl/Tk downloads and access to the Tcler's Wiki are all
available online at the Tcl Developer Xchange. The latest books,
tutorials and demos are also accessible from this site along with the
Tcl core development team that steers the ongoing evolution of the
language.


Contact:
Amy Hesser
Hesser Communications Group
amy_at_hessercommunications.com
312-933-8324

From: Eckhard Lehmann <eckhardnospam_at_gmx.de>
Date: Thu, 01 May 2008 13:28:26 +0200

Hi,

two questions on the -type field of the Attribute class:

1)
There is obviously no documentation on the available types? I needed to
force an error on a wrong -type that told me all the available types

2)
Is there a -type that denotes a string? There is alnum and alpha, but I
mean ordinary strings that can contain arbitrary (utf-8, ISO-8859-1
etc.) characters? Or alternatively, are the types extensible?

Background of this question: The -type of an attribute seems to be a
useful invention for an automated persistency framework for databases.
The problem with that automation is currently that you can not really
generate SQL automatically for XOTcl attributes, because you don't know
their exact storage types from looking at the classes.
If it was possible to assign the proper -type to attributes (e.g.
"text", "date", "bytea" ...), then I could see two cool possibilities
for a persistency framework:

a) create XOTcl classes automatically using meta information of the
database, and -type as validator
b) create CRUD and select statements automatically from XOTcl classes,
using -type for the proper quoting/format that the database expects

At least for the basic types this could be helpful.

Any thoughts?

-- 
Eckhard