olpa, OSS developer

python libxml2 dita

For correct transformation of DITA files (XML-standard for modular documentation), it is necessary to pull information from DTD (document type definition). In my python code, sometimes I did get this information and sometimes not. Now I’ve tracked the source of instability and corrected the code.

(more…)

Sometimes I dump binary data into XML. Being aware of illegal bytes (0-8,B-C,F-1F), I encode everything in base64. But there is a nice alernative way, just revealed by Roger Costello in the xml-dev maillist:

Move any illegal characters into the Private Use Area: for each illegal character add hex E000.

Google Web Toolkit (GWT) allows developers to use the Java programming language to build no-compromise AJAX applications. After announcing my project in its discussion group, I got a reasonable question: “Can you explain how this could be used within the GWT client code?”

(more…)

I’ve announced Generative XPath in few places. This entry is to assist tracking responses. xml-dev | comp.lang.xml | Google Web Toolkit | google-ajax-discuss | comp.lang.scheme(.lisp) | ssax-sxml.

Unfortunately, I’m not going to speak at gttse’2007 participants workshop. My extended abstract (Recursion-free XPath 1.0 implementation) was rejected, the comment from the reviewers is below.

(more…)

I like Prague, it’s a very beautiful city. My contribution to XML Prague 2007:
* paper “Generative XPath”
* presentation slides
* poster XML to beautiful documents, and how it looked like

Generative XPath (0.9.1) is an XPath 1.0 processor that can be adapted to different hierarchical memory structures and different programming languages. Customizing Generative XPath to a specific environment is several magnitudes of order easier than implementing XPath from scratch.

(more…)

I’ve just sent an extended abstract for the XML Prague 2007 conference. I hope it will be accepted.

(more…)

The expression “1+2+3” is converted to:

(list-ec
    (:list e1 (gx:. gx:unit gx-ffi:number gx:fido (gx:unit 1)))
    (:list e2
      (gx:. gx:unit gx-ffi:number gx:fido
        (list-ec
            (:list e1 (gx:. gx:unit gx-ffi:number gx:fido (gx:unit 2)))
            (:list e2 (gx:. gx:unit gx-ffi:number gx:fido (gx:unit 3)))
          (+ e1 e2))))
  (+ e1 e2))

(more…)

I’ve dumped some my thoughts to text. Result is a draft of a possible paper: “Towards s-expression based XPath/XSLT implementation“.

Recently I found the paper “XPath Filename Expansion in a Unix Shell” (HTML, PDF) by Kaspar Giger and Erik Wilde. I’m pleased the authors have referenced my developments (“find with XPath over file system“).
(more…)

Many XPath tutorials use file paths as an analogy of XPath. While it is ok from a high-level point of view, the analogy is misleading and actual technical implementations (one, another, my) are kludge (at least, my implementation). Here are some issues.
(more…)

Finally, my GTTSE 2005 photos are online. The start page is approximately 2Mb, and larger photos are of 300Kb-1Mb size. Unfortunately, I can’t describe how great was the event. Instead, read “Resume from GTTSE Summer School” by Steen Brahe.

Finally, “with-param” in the Scheme function “x:apply-templates” works. It took some time because I forget an experience with making “mode” working. Again, parameter name should be in the dictionary. Unfortunately, namespaced parameters doesn’t work, probably due to a bug of libxslt. Reported, waiting.

From the mail discussions: www.askemos.org. “This is actually a Scheme VM in byzantine synchronisation over a P2P network with some administration free (root-less) permission control system.” The point of interest for me is “Scheme VM”.

I’ve submitted my new project XSieve to the Google’s Summer of Code program.

(more…)

I’ve published the article “Reusing XML Processing Code in non-XML Applications” ([PDF]) version 1.0 and posted announces to different forums.

(more…)

Some time ago I submitted an article to the Generative Programming and Component Engineering (GPCE’05) conference. Article is rejected, but to my great surprise I’ve got useful and inspiring comments.

(more…)

A small test case revealed weak points in my code. Fixing each point was making the code worse and worse. Fortunately, I got insight. Why not to use a fake node? I did it, and code became simpler, hundred lines smaller, and I automatically fixed a weak point for which I had had no idea for a workaround.

A small firm has a Subversion server located in a local network. The network is secured by a firewall. The task: give access to the Subversion server from the outside, both to Linux and Windows users. The solution should be as secure as possible.

(more…)