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to michael:

maybe you can show some rebol pseude code, how to read all chapters 
from a book.xml file, so we had some nice use case to think about

... using a XML port

carsten: I have to think about it ... quite some time I even used 
a java xml library

Some more ideas:

I think the idea behind rebxml is great - build some common format 
representing xml in REBOL blocks. Some more ideas/wishes:

- maybe rebxml could be changed to ignore ignorable whitespaces, 
thats all whitespace between elements like line feeds, indention 
(beside elements with xml:space="preserve"), the block would be much 
smaller, but so the rebxml2xml script requires maybe a refinement 
/prettyprint with automatic indention

- I think rebxml is a great idea, but for easier parsing maybe some 
words would help that indicate the beginning of special nodes like 
[elem "chapter" attribs [name "value" id "0815"] [ elem "sect" attribs 
[ id "5x12"] [ ....]]
does it make sense?

Carsten, I think, your removal of LOAD in the error solution, you 
posted, does lead to some problems. But there also is a problem with 
the script, as it is now. I'm doing some investigation.

something called runit exists AFAIK. But i never understood what 
the advantage in regard to rebol is. i can just write a testscript 
and call it?

But if you have 10 or more you can collect them, maybe they print 
some report (time, errors etc.) and you avoid things like this: carstens 
removes a "load", it works for him, but breaks another piece of code. 
And often nobody writes test scripts/code. And the test scripts, 
if available, are always a good code base to learn how the real script 
should be used. I'll look into rebol-unit (but only tomorrow)...

together with a bit unix for copy/deep test-directories and a diff 
later.

Carsten, I tried to handle comments internal in RebXML as the tag! 
datatype, but there seem to be a problem with tags containing newlines, 
other tags, etc. as a comment in XML can. So my solution doesn't 
work. Now I consider, if comments should be stored as strings in 
RebXML, but then there's the problem to distinguish them from data 
strings.

A solution could be to do, as you suggested with node words (elem, 
attribs), which could be extended with the word: comment

> Some more ideas:

I think the idea behind rebxml is great - build some common format 
representing xml in REBOL blocks. Some more ideas/wishes:

> nodes like [elem "chapter" attribs [name "value" id "0815"] [ elem 
"sect" attribs [ id "5x12"] [ ....]]

Our first solution (actually the one we're now using in production) 
was similar to that. But it brings a lot of ovehead to the data and 
the data adressing is far to be intuitive : aaa/elem/bbb/elem/ccc/attribs/name 
instead of aaa/bbb/ccc/name for instance. Not the most suitable solution 
as we experimented.

It would be triviel to parse a RebXML block and add the node names 
(elem, attribs and comment), if that format is desired, but RebXML 
itself should be with as little overhead as possible.

BTW, we called our project (not having find a better name): EasyXML. 
Just for the record :-)

In this case, perhaps you could consider the comments as a special 
case of an empty tag, marking it with an heading "--" for example. 
It would not create a lot of overhead i think

Christophe: Thanks for the rebol-unit link, how different is EasyXML 
from rebXML?


Another question: how near to XML 1.0 should the REBOL implementation 
be? If yes, so the block format needs a document block with doctype 
information and children (elements, text, comments, processing instructions 
and attributes) and of course namespaces. How about DTD support and 
external entities like this:
<?xml version="1.0"?>
<!DOCTYPE root [
  <!ENTITY test SYSTEM "external.xml">
]> 
<root>
  &test;
</root>
They don't need to be preserved but should be resolved.


Geomol: I fully agree with you, to have a small format, but I think 
it would be nice if it supports the basic XML nodes. These are only 
my wishes of course ..., maybe we don't need extra words for elems 
and attributes, only for comments or PIs as special types of element 
children?

Carsten: "how different is EasyXML from rebXML?"
I don't know :-)

The most of our REBOL development is conditioned by the need of my 
job. Now I need an easy way to access to the parsed data. Xpath is 
an easy way. So we are creating a structure which facilitate the 
access to nested data. And it's fun :-)

Now it could be john create something similar, and that we like it 
and adopt it. Who knows ?

Has anybody think about a rigth data structure to use with a SAX-implementation 
? I was thinking of the hash! and its performence for level 1 data 
retrieval. Perhaps an appropriate data structure could be a binary 
array labeling each element with a concatenation of the access path. 
Like this:
<aaa attaaa="aaa1"><bbb>contentbbb</bbb></aaa> 

becomes

make hash! [aaa id2 aaa-attaaa "aaa1" aaa-bbb "contentbbb"]

based on a mapping table

 make hash! [id1 aaa id2 bbb]

or something similar...

just a rough though !

SAX apis don't work like that. They generate a series of events, 
not a series of data.

I thought SAx was about finding the most suitable data structure 
- not a tree representation, which is DOM.

I don't know if the event handling part is mandatory (BTW, to whom 
?).
isn't all about accessing XML data the best way a PL can ?

Ok, I'm not a SAX specialist :-/
for my understanding, could you give an example of how 
<aaa attaaa="aaa1"><bbb>contentbbb</bbb></aaa>
should be SAX-handled ?

If you say "I want to do a SAX-style XML parser", you mean event 
handling. Other data models have their own apis to copy, or don't 
so you have to come up with something new :)

As for that data, let's assume a normal, fine-grained model. I'll 
just list the events:

tag "aaa"
attribute "attaaa" "aaa1"
end tag
tag "bbb"
end tag
contentbbb
tag "/bbb"
end tag
tag "/aaa"
end tag


If you use a more coarse-grained model, you could have an event for 
a whole tag, its attributes, namespaces and such, rather than seperate 
events for each. This might be more appropriate for a more powerful 
language like REBOL. Fine-grained events are really more appropriate 
for languages with poor data structure support, like C or rebcode.

The important thing is to make sure that the events or data structures 
are a good map of the semantic model of XML. They have standards 
abut that too.

Did you have a look at the source of 'parse-xml ? Is this what is 
meant to be event-driven ?

No, parse-xml generates a (broken, incomplete) DOM tree. Gavin McKenzie's 
xml-parse is more like a SAX parser.

hum... i will digg a little more into the the theory i think. I had 
learnad another approach to that.
Thanks anyway for showing the way !

I've also had a look inside xml-parse, it seems to be really like 
SAX - ready to use. But nobody is maintaining it, I think. As far 
as I understand, somebody could create a Handler to get the desired 
block structure (for instance a Handler for RebXML or any other model). 
I have to learn about this in REBOL.


A question: how can I measure memory for a block or an object tree 
in REBOL?

RebXML: I did some testing with rebxml, the documents I used can 
be found here:
 http://www.simplix.de/rebol/resources/xml/xmltests.zip

There is also a simple script that reads the XML docs in and writes 
them back.

Some problems I found:
- empty attributes, I have fixed this in the zip

- entities in content: all should be escaped, because they can be 
found there, otherwise a " gets "
- comments after last element missed
- comments before first element - missing line feed
- missing PIs in output


Another question: encoding - it seems that all output files will 
be written in iso-8859-1 ?

About memory for block or object, If you mean in bytes internally 
in REBOL, I don't know. But you could save the block or object to 
a file and see a size that way. You can of course see the length 
of a serie with: length?

Carsten, a recursive function to count length of blocks with nested 
blocks:

total-length?: func [b [block!] /local n] [
	n: 0
	foreach e b [if block? e [n: n + total-length? e] n: n + 1]
]

John: Thank you, I'll play with it.

I found this python tool - maybe some interessting ideas there:
http://uche.ogbuji.net/uche.ogbuji.net/tech/4suite/amara/quickref

He uses objects but I like the idea for accessing xml - replacing 
the dots with slashes it looks for me like REBOL:
doc/a/nodeName
doc/a/b/1
...
doc/xml

Catching up a little.  Be interesting to summarise this thread as 
there are many different ideas expressed.  rebxml looks interesting 
for loading, saving and likely extracting xml, but still perhaps 
difficult to manipulate.

I've also noticed a tendency to kick the DOM (no doubt for good reason) 
-- though worth noting that it is a complete api to xml and it is 
a standard api, I wouldn't underestimate the value of the latter, 
particularly when it comes to Rebol advocacy...

RebXML is meant for conversion to/from the RebXML format and other 
formats (incl. XML). I use the RebXML format with NicomDoc, which 
makes it a lot easier to handle document formats. Let's say, you've 
got an XML file, and want to convert it to a format easily read by 
some application, then you first use xml2rebxml to get the XML file 
to RebXML format. Then make a converter from RebXML to the final 
format by renaming the rebxml2xml script and change it to do the 
output, that is wanted. rebxml2xml holds the structure of the RebXML 
format, so it's easier to start with that script. Search for "output" 
in rebxml2xml.

Maybe I should make a converter from RebXML to some format very easily 
manipulated directly within REBOL, like the python tool, Carsten 
found.

Using DOM methods, you can do this albeit clumsily, but completely. 
 All through a set of standard functions, with no need to manipulate 
the structure directly.

Any less than you'd want a 10mb Rebol interchange file?  What % of 
cases would this be an issue?

in the moment i play a little bit with xml-parse.r, it has a lot 
of things done, some are still open (like  <!ENTITY ...> parsing) 
and it is like SAX - I try to implement some handlers to learn REBOL, 
but it's still in progess. A benefit of xml-parse is, that there 
would be only one parser and some kind of standard API and the handler 
could then generate rebxml or some other desired format

DOM: in java APIs there were allways problems with dom - big amount 
of memory, not optimized for a language, so there was a need for 
optimized tools like JDOM, XOM or DOM4J, they all prefer SAX for 
parsing and have their own internal model - of course the API is 
special for all these tools and no standard like DOM

Has somebody already give a try to a SAX implementation ?

xml is such bloat.. I am parsing xml these days and for two characters 
of data, I often have a 100+ characters of nested stupidity.

an empiric test (subjective to the xml structure and tag names obviously, 
but this IS a real world xml file)

Agreed.  So, write a Rebol block ML that does everything as well 
as XML, and we will support it.

XML was intended to be a simplification of SGML.

But they forgot to ask first "why is SGML apparently some complicated?"

So they ended up adding back in most of the complications in an ad 
hoc way.

XML was a simple 2 page spec originally.

I'm on a list discussing, inter alia, CCR .. which stands for continuity 
of care record. It's XML, and so guys are saying it's taken them 
50,000 lines to write the parsing code etc.

I think not, Graham .... we have such a problem ... big corporation, 
we try to define xml formats. The trouble is, big products do wrap 
it for you, but what about smaller companies?

If you need a simple XML spec, don't forget my RebXML: http://home.tiscali.dk/john.niclasen/rebxml/
(Only a couple of pages.)

It's an easy way to work with XML inside REBOL, and on the same page 
you'll find scripts for converting between XML and RebXML.

I remember talk a few years ago, that MS would make their .doc format 
XML based. And people thought, that would mean, it would become an 
'open' format, which could now be read and written by any wordprocessor. 
If you have somehing like:
#{78797A7138373837}
in binary, and choose to make it into XML:
<xyzq>8787</xyzq>

does that make you know, what it mean? No, of course not. Some MS 
employee later told in an interview, that MS of course would guard 
their IP - 'intellectual property'. I don't know, where the story 
ended, and I don't care much, as I keep away from MS formats.

saved out a 15 cell spread sheet in microsoft xml yesterday...  58kb 
of data HAHAHHAHAHAHAHA

Geomol, just looked over rebxml...  I've build a similar engine, 
even simpler actually.  but it might become a little bit smarter 
in a few weeks... maybe supporting more of the XML 1.0 specs like 
&chars conversion and such.

my tool currenctly loads 1MB of xml tags in under a second.  its 
almost as fast as load/markup.

yet builds a nested block of blocks much like RebXML.

it does all in one shot.  I read through the string once and have 
a nifty recursion with tail handling.

Geomol,  you might just have made yourself a new user :-)  I'll try 
to stress-test RebXML next week, gauging speed, features and stability.

We have done a little in Qtask.  WE save the tasks as XML (and call 
it XLS so that Excel can load it).
We will be writing an RSS reader soon.

there's a new script in the library %rebelxml.r ( not sure why it 
isn't rebolxml.r )

I'm using rebxml as the loader and then write a dialect over it to 
convert to my preffered (easier to use) block format.

that's my 2 cents.  and a 2 minute overlook of rebelxml.r

it seems powerfull, but I had a hard type getting it to work.  I 
WAS pressed for time though.

1) people want XSLT and XPath in rebol, because it's the standard 
and so on.

2) people want a dialect that offerst XSLT/XPath-like functionality 
to work on REBOL trees (as opposed to XML)

3) noone cares about representing data as trees in REBOL because 
dialects are much better anyway

just to join the dots.....There is also a DevCon2008 thread on the 
Mailing List:

Nick, that's cool stuff. One question: do you use the Flash Media 
server with a custom app or  an Adobe solution (Acrobat connect pro)?

Maarten, it's FMS with a custum app (one that I've only tweaked slightly 
- not my creation).  Reichart, I worked for a long time towards a 
Rebol videoconference solution, and this just d

completely beat any of my efforts.  It has opened some new interesting 
doors for me, though (now learning Openlaszlo,  Red5 server, some 
Java, and Openmeetings - that's the next best platform and bit of 
 software for this type of work).  I'd love to do more work on Rebol 
videoconferencing some day.  I think it'd be a killer app...

This is my first time posting to Altme - I'm comfortable communicating 
here to organize Devcon activities.  A group demo may be the easiest 
way to prepare, if we can find a convenient common time.  I'm in 
Eastern time zone - during the week, I'm typically free late mornings, 
early afternoons, and then again after 10pm.   I can be reached by 
email at nick ---a t---  musiclessonz ---d o t--- com for anything 
personal :)

Nick, glad to finally see you post.  I assume you usually monitor 
the web output of the this world.  I hope we do eventually get a 
video conferencing solution in REBOL.  I don't see it happening before 
REBOL3 hits though.

just a note - DevCon 2009 is going to happen in Prague, Czech Republic 
- the real devcon, not the virtual one :-)

as for video and REBOL, we are wrapping ffmpeg, so many video formats. 
But of course, having streaming server is completly different topic. 
And yes, video for R3 will be a killer app ...

Hi Paul - yes, I've been lurking via html :)  Off topic:  I dabbled 
a bit with the Windows API and have a simple working webcam viewer, 
and also a working remote video client that produces usable video 
from simple image refreshes.  I need to explore the audio api to 
understand how to capture and pass audio frames across the net - 
I've got plenty of code from other languages - just need  to convert 
all those api calls to Rebol and see if there are any performance 
issues, but I suspect that a very simple point-to-point app like 
that could work in Rebol2.  To make it practical for real use, there'd 
need to be a little server/repeater app to pass data back and forth 
between clients that are behind routers.  Not so crazy difficult, 
I don't think...

To prepare for Devcon, I made a sign up form for 3 dates/times that 
I'm available to do group demo/prep work.  Please add your name if 
you'd like to meet at any of those times.   http://rockfactory.us/events/devcon.html
 .  The meeting room will be http://rockfactory.us/rooms/room20. 
 I'll confirm the times/dates at the above page, once a few people 
have signed up.

Well at least you got work Nick.  That is a nice blessing right now.

I'm looking forward to watching Rebol evolve with R3, and hoping 
to play a part :)\

Well I'm looking forward to a virtual Devcon.

A sign up checklist was created to find out who is interested in 
joining us.

We've already got 4 sign ups for next Wednesday, December 17th, noon 
EST, so I've marked it as a confirmed event, and I'll plan on being 
online then to help show how to use the system :)

I have a dental apointment about 1 our in, but will make the first 
part.

Anyone who wants to speak with me or others on Wednesday should have 
a microphone and headphones already attached to the computer.  Please 
use headphones instead of speakers to avoid echo (echo can get to 
be a really big problem without headphones).  To test your setup, 
including your audio/video, please use this page:  http://rockfactory.us/videos/videogallery_viewer.html
.  Please let me know if you have any questions!

- Times Roman font on front page (needs a better looking welcome 
page)
- Stealing Vista UI on video is a copyright infringement.

- Bottom controls (just under 3 video frames) were hidden when I 
first came in (I needed to pull the iframe down).
- "Who is online" needs to be a list on the left side.

- The chance to send video took about 3 minutes, so I did not see 
how to do this.  The video box should say it will do this for you 
at some point.

==================
Current video list
==================

- Times Roman font is ugly

- Welcome page needs a better looking welcome page (put it in a nice 
standard box)
- Stealing Vista UI on video is a copyright infringement.

- Bottom controls (just under 3 video frames) were hidden when I 
first came in (I needed to pull the iframe down).
- "Who is online" needs to be a list on the left side.

- The chance to send video took about 3 minutes, so I did not see 
how to do this.  The video box should say it will do this for you 
at some point.
- Chat box shows "viewer n" as opposed to <name>
- Each iframe seems to come up too small.
- Chat buffer is too small (and allows too few characters.

- Echo is a big problem (Other systems have this problem, but TeamSpeak 
less than others).

==================
Current video list (ver 2)
==================

- What is the actual architecture here?

- Times Roman font is ugly

- Welcome page needs a better looking welcome page (put it in a nice 
standard box)
- Stealing Vista UI on video is a copyright infringement.

- Bottom controls (just under 3 video frames) were hidden when I 
first came in (I needed to pull the iframe down).
- "Who is online" needs to be a list on the left side.

- The chance to send video took about 3 minutes, so I did not see 
how to do this.  The video box should say it will do this for you 
at some point.
- Chat box shows "viewer n" as opposed to <name>
- Each iframe seems to come up too small.
- Chat buffer is too small (and allows too few characters.

- Echo is a big problem (Other systems have this problem, but TeamSpeak 
less than others).


= Screen shot capture = 


- Change [Download screen sender] to [Download Windows Screen Sender]. 
 Or just ad Windows icon.

- Add icons to all functions at bottom, like an upload icon for Upload.

- Rename [RockFactory] to same name as it thinks it is PNGShot.exe. 
 My virus catcher was NOT happy about this program running.

If there is a way to get the names in the broadcast/viewer one, i 
think it would be almost perfect.

I'll get a better text chat together, with name :)

Reichart, I'll add a file area, with a link at the top of the viewer 
page, and update the screen sender

Wow, I can't even make a virtual DevCon :(
Neither of those pages work for me.

BrianH, it'll only work 1 at a time - that's probably why you're 
not seeing it.

I see the viewer page, but the Live Video Broadcast frame just surrounds 
a grey box.

It will only allow one broadcaster at a time, and someone currently 
has that page open

That wasn't DevCon - just a meeting to prepare :)

Nick, I hope that guest logins timeout, because closing the browser 
window makes your login inaccessible. Reloading the page orr even 
a refresh loses your login, and then leaves your old alias logged 
in, blocking any attempt to relogin with the same alias. There is 
currently a BrianH logged into presenter chat, so I hope you can 
log that ID out because I can't. Closing the window should log the 
person out.

The presenter chat interface is too tall to fit on a 1024x768 screen, 
let alone the 1024x600 on my netbook. It would help if you got rid 
of
  <tr> 
    <td align="center">&nbsp;</td> 
  </tr> 

that is above the row where the flash is embedded, or better yet 
replace the whole table with a
  <div style="text-align: center">...</div>

However, even when you reference the the flash itself, it has some 
kind of title at the top that pushes the interface down so far that 
you can't see the text entry field on a 1024x768 screen. This is 
a bug in the flash.

Ahh, yeah think that was just me though because I didn't use a headset 
and mic.

I thought it was adequate for a presentation.

Were you using the Presenter Chat interface for your broadcast, or 
the rooms interface? For that matter, do either of you use a laptop?

Just shows a still image.

Hey Brian, maybe add that to your list - to  have a refresh sent 
 to the browser after someone leaves the broadcast

a devcon2008chat group could be created

That is what this is already, no need for a rename.

but to retrieve the usefulls links we need a better place

When the day comes of the dev con itself, we might make a bunch of 
Rooms here so we all have a place to talk.

Room - Current speak
Room - Ask a question now
Room - Lobby (place for people to talk with out annoying others)

If we are willing to pay we can use the Adobe service as well. This 
worked but I couldn't get the spund to my headset, if I recall (the 
brief period before my ADSL went down) it was only 3 at a time. I 
think they have a pay-as-you-go. The money would be like the virtual 
conference fee.

Anyway, cool stuff.