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From: Gustaf Neumann <neumann_at_wu-wien.ac.at>
Date: Sat, 13 Dec 2003 21:49:58 +0100

 Dear XOTcl community,
 
 i am pleased to announce the general availability of xotcl 1.1.1.
 Changes relative to 1.1.0 are:

  - Improved portability
     * for Mac OS X (many thanks to Daniel Steffen)
     * freebsd 4.9 (many thanks to Marc Spitzer)

  - configure can run outside of xotcl-tree and
    can install to a different directory. Example:

            % mkdir -p /tmp/xotcl/unix
            % cd /tmp/xotcl/unix
            % ~/xotcl-1.1.1/unix/configure --with-all
            % make
            % make test
            % make install DESTDIR=/tmp

  - several fixes and improvements such as
     * added option --with-tkinclude for configure
       (only needed, when built with optional --with-xowish)
     * made gdbm work when compiled with threads enabled
     * fix for initialization of stubtables in gdbm
     * fixes for HTTP support (return format of values in
       HTTP OPTION command made windows explorer hang)
     * easy provision for redirects in HTTP server

 best regards
-gustaf neumann

-- 
Univ.Prof. Dr.Gustaf Neumann
Abteilung für Wirtschaftsinformatik
WU-Wien, Augasse 2-6, 1090 Wien

From: Kristoffer Lawson <setok_at_fishpool.com>
Date: Mon, 13 Aug 2001 16:52:10 +0300 (EEST)

On Mon, 13 Aug 2001, Gustaf Neumann wrote:

>
> The right way to query instprocs is via "info instargs" and
> "info instbody" rather than "info args" and "info body" or
> the tcl counterparts...

Well, as mentioned, this does not really work in my case. I do not know
beforehand whether a proc is an instproc or a per-object proc. I am using
meta-programming and using methods as templates for other dynamically
built methods. When the API gets the name of the method, it asks for
the body and arguments, so it can create another method with that
information. When looking up that information it now assumes that the
given method name is an instproc and asks the class -- but this is not
a general solution.

As pointed out by Artur, there are ways to do this, but they're pretty
complex, so I am looking for a straightforward way of asking information
about a method, without caring about whether it's inherited or not.

         - ---------- = = ---------//--+
         | / Kristoffer Lawson | www.fishpool.fi|.com
         +-> | setok_at_fishpool.com | - - --+------
             |-- Fishpool Creations Ltd - / |
             +-------- = - - - = --------- /~setok/

From: Gustaf Neumann <neumann_at_wu-wien.ac.at>
Date: Thu, 08 Dec 2005 12:43:22 +0100

Hmm, are you sure? the script you have sent does not produce the message
you are indicating....

~/scripts> set ::xotcl::version
1.3
~/scripts> set ::xotcl::patchlevel
.8
~/scripts> Class X -parameter {
> {y y0}
>}
::X
~/scripts> X instproc init {args} { puts "[self] init '$args'"; next }
~/scripts> X instproc y {args} {
> set x [next]
> puts "[self] y '$args'"
> set x
>}
~/scripts> X create x -y y1
::x y 'y0'
::x y 'y1'
::x init ''
::x
=============================
however, most probably it is not doing what you might be expecting.
your method y overwrites the setter method of parameter y, therefore in
this example, not much happens in the next of method y.

maybe you had in mind to overload the setter/getter method, which you can
do e.g. with a mixin (see below)

Class X -parameter {
    {y y0}
} -instmixin [Class new -instproc y args {
  puts "[self] [self proc] $args"
  set x [next]
  puts "[self] [self proc] $args setter returns <$x>"
  return $x
}]

X create x -y y1
puts x.y=[x set y]

From: Gustaf Neumann <neumann_at_wu-wien.ac.at>
Date: Wed, 01 Mar 2006 10:05:43 +0100

Dear Matthew,
> The extra call to destroy occurs when the command interpreter closes, so
> must mean that MyBase was not properly destroyed because "next" was not
> called. This is probably the intended behaviour, but it is difficult to work
> it out from the examples given in
> http://media.wu-wien.ac.at/doc/tutorial.html.
>
you are right, the documentation should be improved. I have just added a
paragraph
adressing this point.

The destruction of objects is performed by the c-level method destroy of
::xotcl::Object.
The method destroy is a method like every other method in xotcl, asides
from its
side-effects, it is no way magic or special. If an application class
overwrites the
destroy method, and does not call "next", Object->destroy will not be
called, the
object will not be destroyed.
> Can somebody tell me the creation and destruction processes that go on
> "behind the scenes" in XOTcl?
>
You can ask xotcl to tell you, what's going on. Consider the following
filter
method implementing a trace. Before and after each invocation of a method,
the filter spits out a single line. We register the filter for all
instances of
all objects (as an instfilter for Object):

   Object instproc f args {
     puts "call [self]->[self calledproc]"
     set r [next]
     puts " [self]->[self calledproc] returns '$r'"
     return $r
   }

   Class C
   Object instfilter f
   puts ==================
   C c1
   puts ==================
   c1 destroy
   puts ==================
   Object instfilter ""

If we run the script, we get the following output.
==================
call ::C->c1
     ::C->c1 returns ''
call ::C->unknown
call ::C->create
call ::C->alloc
     ::C->alloc returns '::c1'
call ::xotcl::Class::Parameter->searchDefaults
     ::xotcl::Class::Parameter->searchDefaults returns ''
call ::c1->configure
     ::c1->configure returns '0'
call ::c1->init
     ::c1->init returns ''
     ::C->create returns '::c1'
     ::C->unknown returns '::c1'
==================
call ::c1->destroy
call ::C->instdestroy
     ::C->instdestroy returns ''
     ::c1->destroy returns ''
==================

If we create an Object via "C c1", we call a method c1 of Object. since this
is not defined, "C unknown" is invoked. For all classes, the predefined
unknown handler "create"s an object with the specified name. create
initiates the creation protocol,
 - starting with "alloc" (registering the object as command, allocating
memory),
 - calling "searchDefaults" (for setting the default values specified
via parameters),
 - calling "configure", to overwrite some of these values and to specify
additional values,
 - calling "init" to perform additional application-level
initializations, based on
   the default and configured values.

destruction is much simpler. "destroy" is called on the object level,
"instdestroy"
is the counterpart of "alloc" on the class level (the class manages the
object,
allocates and destroys it, knows its instances, etc.)
> Also, it would be helpful if the differences between XOTcl and other OO
> languages, say C++, were highlighted as I know I have made assumptions which
> turn out to be wrong.
>
There are certainly many differences between a highly dynamic oo
language and e.g. C++.
Maybe some can start writing his gotchas into a wiki page. See as well
the distinction
between call-oriented vs. object-oriented in

   http://mini.net/tcl/XOTcl

Hop this helps


-gustaf

From: Gustaf Neumann <neumann_at_wu-wien.ac.at>
Date: Mon, 23 Jul 2007 21:15:09 +0200

Hi everybody,

due to the reported problems, we provide a pre-release of xotcl 1.5.4.
http://media.wu-wien.ac.at/download/xotcl-1.5.4.tar.gz

Below is a list of the changes in this trunk since the release of
xotcl 1.5.3. Ben, please check, if this solves your problem.
Artur's case seems more complicated, i don't see the relation
to the event loops in the fixes below.

-gustaf neumann


2007-07-23 <Gustaf.Neumann_at_wu-wien.ac.at>
    * Pre-Release of XOTcl 1.5.4

2007-07-23: <Gustaf.Neumann_at_wu-wien.ac.at>
   * fixed a bug with empty argument names
      (Many thanks for Stefan Sobernig for reporting the bug)

2007-07-03: <Gustaf.Neumann_at_wu-wien.ac.at>
   * allow to call methods from the class to be called
     from slot objects (Many thanks for
     Nico L'INSALATA for noting this problem).

2007-06-05: <Gustaf.Neumann_at_wu-wien.ac.at>
   * Fixed spelling mistakes in the tutorial
      (Many thanks to Robert Hicks for reporting)

2007-05-27: <Gustaf.Neumann_at_wu-wien.ac.at>
   * Fixed potential error with default values for parameters
     starting with a "-". (Many thanks to Shishir Ramam
     for reporting)

2007-03-16: <Gustaf.Neumann_at_wu-wien.ac.at>
    * fixed a bug where a Tcl call adds a namespace to an object,
       but xotcl did not notice it. (Many thanks for Stefan Sobernig
       for reporting the bug)

2007-01-14: <Gustaf.Neumann_at_wu-wien.ac.at>
    * fixing error message propagation for methods called via
       configure. (Many thanks for Kristoffer Lawson
       for reporting the bug)

2006-12-12 <Gustaf.Neumann_at_wu-wien.ac.at>
    * changing "test == " to "test =" as required by FreeBSD
      (many thanks to Martin Matuska for providing
      the patch)

2006-12-07 <Gustaf.Neumann_at_wu-wien.ac.at>
    * MinGW patches
      (many thanks to Martin Matuska for providing
      the patch)

From: Artur Trzewik <mail_at_xdobry.de>
Date: Thu, 29 Jan 2004 19:03:07 +0100

Hi!

New Version of XOTclIDE 0.58 is released.
http://www.xdobry.de/xotclIDE

changes:
- New plug-ins:
 - FileBrowser - simple gui file manager that can
          mount mk4 and zip archives
 - SQLBrowser - gui for sql queries with some goodies as
      word completion, result show in TkTable and DB-Schema view.
- version control state of components and classes are displayed in differently
colors
- better code completion
- for another changes see change-log file

ATKSQLBrowser is distributed also as separate and stand-alone
application per Starkit technology.
http://www.xdobry.de/atksqlbrowser

I have also separated XOTcl sql interface to XOSQL package.
That provide uniform access to several Tcl interfaces:
mysqltcl, sqlite, postgres, tclodbc
and have uniform Tk connection dialog.
http://www.xdobry.de/xosql

Artur Trzewik

From: Gustaf Neumann <neumann_at_wu-wien.ac.at>
Date: Sat, 27 Nov 2004 23:12:04 +0100

Dear XOTcl Community,
XOTcl 1.3.3 is available. Major changes relative to 1.3.1 are:

  - Qualitative Improvements

     * Improved code quality:
       + fixed possible segmentation violations in free memory reads
         (many thanks to Zoran Vasiljevic for his help with purify)
       + fixed "self callinglevel" when uplevel was called from uplevel
       + fixed nonposargs
       + fixed configure in connection with enable-symbols and
         for aolserver configuration
       + extended regression test

     * Improved Functionality
       + Producing error message when a non-existing proc/instproc
         is tried to be deleted
       + fixed exists method for objects with namespaces by using
         a namespace resolver
       + fixed return code for unknown handling in next
       + reduced memory consumption for objects and classes with procs/instprocs
         of about 14%

     * Improved Documentation

We will annouce XOTcl 1.3.3 on c.l.t, when we have the windows binaries

Greetings
-gustaf neumann

-- 
Univ.Prof. Dr.Gustaf Neumann
Abteilung für Wirtschaftsinformatik und Neue Medien
Wirtschaftsuniversität Wien, Augasse 2-6, 1090 Wien

From: Gustaf Neumann <neumann_at_wu-wien.ac.at>
Date: Wed, 17 Oct 2001 21:07:36 +0200

 Dear XOTcl users,

 we just found a small glitch in xotcl 0.9, which will happen only in rare
 situations. However, if you see an error message "can't instvar to link",
 drop us a short note, and you get immediately a fix. Since the bug appears
 to be pretty rare, we will wait with the patch release a little.

 best regards

-gustaf neumann

From: jim <j_marvin_at_localnet.com>
Date: Thu, 11 Mar 2004 03:39:41 -0500

sorry for being fickle.
i just cant.
now is not a good time to use tcl on
the web for me. maybe in the distant future.
i still really like tcl for non - web related things.
thanks anyways.
 
dont open any attachments from me.
i am investigating a virus .
i didnt (knowingly) attach that file that
got sent to the group.
 
later
marvin
 

From: Gustaf Neumann <neumann_at_wu-wien.ac.at>
Date: Wed, 07 May 2008 22:38:40 +0200

Matthew Smith schrieb:
>
> How do I call the methods like push and pop?
Let us assume, you have a class "Stack" defined and
the class stack contains definitions for the methods
(instprocs) "push" and "pop". The class provides these
methods for ins instances. Therefore, in order to
invoke these methods, you will need an instance
of class Stack (an object of the type Stack). One can
create such an instances (e.g. "s1") with the following
command

   Stack s1

Once the object exists, the methods "push" and "pop" can be called via
  s1 push a

or

  puts [s1 pop]

So, the first word of the Tcl command refers to the object
(the instance of class stack) and the second word refers to the method.
If there are more words, these are passed as arguments to the method.

Hope, this helps
-gustaf neumann

PS: The xotcl-core tutorial ist for the OpenACS environment.
There, it is not necessary to include the "package require XOTcl"
and the "namespace import ::xotcl::*". You need these
commands in case you use XOTcl in a tclsh.