index.xml

<?xml version="1.0" encoding="ISO-8859-1" standalone="yes"?>
<page name="index" url="/">

<title>Home page</title>
<banner>
  <img title="CDuce" src="img/cduce_logo.jpg" width="400" height="206"
       alt="CDuce"/>
</banner>

<left>
<p>On this page:</p>
<boxes-toc/>
<p>Under this page:</p>
<pages-toc/>
</left>

<external href="/cgi-bin/cduce" title="Online demo" name="proto"/>
<include file="download.xml"/>
<include file="bench.xml"/>
<include file="papers.xml"/>
<include file="documentation.xml"/>
<include file="examples.xml"/>
<include file="hacking.xml"/>
<include file="mailing.xml"/>
<include file="team.xml"/>
<include file="sitemap.xml"/>


<left>

<p> CDuce ("seduce") is a new typed functional language with
innovative features.</p>

<p> Although CDuce is a general programming language, it features
several characteristics that make it adapted to XML documents
manipulation (transformation, extraction of information, creation of
documents).  
<a href="http://www.w3.org/XML/">XML</a> is a syntax to
describe tree-like documents (aka semi-structured data), and XML
documents often come with a description of their type. The type is
expressed in a system like DTD, or 
<a href="http://www.w3.org/XML/Schema">XML Schema</a>.
XML types play a central role in CDuce.
  </p>

</left>

<left>
<p> All pages of this site were automatically generated from an XML description of
the content by <a href="examples.html#site">the following CDuce program</a>.
</p><p><img src="img/cducepower.jpg" alt="Powered by CDuce"/></p>
</left>

<!--
<box title="Latest News" link="news">
<section title="2003, December 8th, Monday: New addition to papers.">
<p>
A paper on the optimized implementation of pattern matching
in CDuce is now available online in the <a href="papers.html">papers page</a>:
<i>"Regular tree language recognition with static information"</i>.
Another paper, <i>"Greedy regular expression matching"</i>
is a preliminary step in an alternative implementation technique
(non-uniform representation of values). The two papers will be
presented in the PLAN-X 2004 workshop in January (Venice).
</p>
<br/>
</section>

<section title="2003, October 26th, Sunday: New addition to papers.">
<p>
If you want a simple and basic introduction to the theoretical foundations
of CDuce, there is a new entry in the <a href="papers.html">papers page</a>: <i>"A Gentle
Introduction to Semantic Subtyping"</i>.
</p>
<br/>
</section>

<section title="2003, October 17th, Friday: CVS publicly available.">
<p>
You can now download the development version directly from the cvs tree. See instructions at the <a href="download.html">usual place</a>. Be careful, it may not work, and many features are experimental and undocumented.
</p>
<br/>
</section>


<section title="2003, September 23rd, Wednesday: Volunteers sought.">
<p>
We look for volunteers to prepare an emacs mode for CDuce and to implement  a native Win32 or MinGW port. If your are interested please contact 
us.
</p>
<br/>
</section>


<section title="2003, August 16th, Saturday: Version 0.1.1 released.">
<p>
This version has several bug-fixes and encodes reference types. You can now use
<code>:=</code> and <code>;</code>. It is available at the <a href="download.html">usual place</a>. Try this
<a href="http://www.cduce.org/cgi-bin/cduce?example=reference">code</a> on
the on-line demo for an example on how to use them, and refer to the
<a href="manual_expressions.html#ref">manual pages</a> for more
information.
</p>
<br/>
</section>
</box>
-->

<box title="What is CDuce ?" link="whatis">

<p> <b>CDuce</b> is modern programming language, adapted to the
manipulation of XML documents.  It is developed by the <a
href="http://www.di.ens.fr/~castagna/EQUIPE"><b>Languages</b></a>
group of ENS in Paris and the <a
href="http://www.lri.fr/bd"><b>Databases</b></a> group of LRI in
Orsay, two <a href="http://www.cnrs.fr">CNRS</a> labs.
See also the <local href="team">CDuce team</local> page,
and our <local href="papers">technical papers</local>.
</p>

<section title="Getting information">

<p>
The online <local href="documentation">documentation</local>
contains a <local href="tutorial"/> and a <local href="manual"/>.
You can also have a look at some <local
href="examples">examples</local>
of CDuce programs.
</p>

<p>
If you want more information about CDuce you can send a mail to 
<tt>info_at_cduce.org</tt> (replace <tt>_at_</tt> with <tt>@</tt>), or
to the most appropriate <a href="mailing.html">CDuce mailing list</a>.
</p>

</section>

<section title="Online running prototype">
<p> To get a feeling of CDuce,
you can play with the <local href="proto">on-line prototype</local>,
try the examples and modify them. </p>
</section>

<section title="Download">
<p>
You can <local href="download">download</local> a beta
version of CDuce, or a snapshot from the working CVS repository.
</p>
</section>
</box>

<box title="Design and features" link="design">
<p> Our point of view and our guideline for the design of CDuce is
that a programming language for XML should take XML types (
DTD, XML Schema, Relax-NG, ...) seriously into account. 
The benefit are the following:</p>

<ul>
<li> <b>static verifications</b>
(e.g.: ensure that a transformation produces a valid document 
  <footnote>

Valid with respect to validity constraints
that can be expressed by the type system (thus typically excluding 
constraints like <a
href="http://www.w3.org/TR/REC-xml#sec-attribute-types">ID</a> and
<a href="http://www.w3.org/TR/REC-xml#sec-attribute-types">IDREF</a>).

  </footnote>);</li>
<li> in particular, we aim at <b>smooth and safe</b> compositions
of XML transformations, and incremental programming;</li>
<li> static <b>optimizations</b> and <b>efficient execution model</b>
(knowing the type of a document is crucial to extract information 
efficiently).</li> 
</ul>

<p>
Some features particular to CDuce:
</p>
<ul>
<li> XML objects can be manipulated as first-class citizen values:
     elements, sequences, tags, characters and strings, attribute
     sets; sequences of XML elements can be specified by 
     <b>regular expressions</b>, which also apply to
     characters strings; </li>
<li> functions themselves are <b>first-class</b> values, they
     can be manipulated, stored in data structure, returned by
     a function,...</li>
<li> a powerful <b>pattern matching</b> operation can perform
     complex extractions from sequences of XML elements; </li>
<li> a rich <b>type algebra</b>, with recursive types and arbitrary
     boolean combinations (union, intersection, complement) allows
     precise definitions of data structures and XML types;
     <b>general purpose types</b> and types constructors are taken seriously
     (products, extensible records, arbitrary precision integers with interval
     constraints,  Unicode characters);</li>
<li> <b>polymorphism</b> through a natural notion of <b>subtyping</b>,
     and <b>overloaded functions</b> with dynamic dispatch; </li>
<li> an highly-effective <b>type-driven compilation schema</b>. </li>
</ul>

<p>CDuce is fast, functional,
type-safe, and <b>conforms to basic standards</b>: <a href="http://www.unicode.org">Unicode</a>, <a href="http://www.w3.org/XML/">XML</a>, <a href="http://www.w3.org/TR/REC-xml#dt-doctype">DTD</a>,
<a href="http://www.w3.org/TR/REC-xml-names/">Namespaces</a> are fully
supported, <a href="http://www.w3.org/TR/xmlschema-1/">XML Schema</a>
is partially <local href="manual_schema">supported</local>.
</p>

<p>
<local href="bench">Preliminary benchmarks</local> suggest that despite the
overhead for static type verification, a CDuce
program can run faster (30% to 60%) than an equivalent XSLT
style-sheet (we performed benchmarks with
the xsltproc tools from the Gnome libxslt library).
</p>

<p>
The name CDuce was coined by <a 
href="http://www.di.ens.fr/~zappa">Francesco Zappa Nardelli</a>.
</p>

<footnotes/>

</box>

<box title="Research directions" link="research">

<p>Our plans concerning the design of the core language
include:</p>
<ul>
 <li>interface with other languages and type systems
<footnote>
An <local href="manual_interfacewithocaml">
interface between CDuce and OCaml
</local> is currently being
implemented.
</footnote>
 ;
 </li>
 <li>efficient evaluation strategies, high-level optimizations;</li> 
 <li>a module system to support incremental programming;</li>
 <li>parametric polymorphism;</li>
 <li>XML-friendly primitives, to mimic XSLT transformations.</li>
</ul>

<p>
Apart from the core language design and implementation, 
our research projects include:
</p>
<ul>
<li> integration of a <b>query sub-language</b> into CDuce, using
     types as a primary optimization strategy for request evaluation;</li>
<li> study of <b>security</b> (confidentiality, ...) properties in the
     setting of XML transformations.</li>
</ul>

<p>
We wrote several <local href="papers">technical papers</local> about
the language design and its theoretical foundations.
</p>

<footnotes/>

</box>

<box title="XDuce and CDuce" link="xduce">
<p>

The starting point of our work on CDuce was the
<a href="http://xduce.sourceforge.net/">XDuce</a> language developed
at the UPenn DB group. Many of CDuce features originate from XDuce.
Some of our achievements:

</p>
<ul>
<li>integration of first-class and overloaded functions, arbitrary boolean
    connectives, and extensible (or not) records, to the semantic
    definition of subtyping;</li>
<li>a subtyping algorithm without backtracking;</li>
<li>extending pattern matching to capture non consecutive
    subsequences; removing tail condition for exact matching
    (they arrived independently to another solution);</li>
<li>efficient evaluation model that takes profit of static type information;</li>
</ul>
<p>
Of course, the work on XDuce continued during our, and they
developed nice ideas: mixed attribute-element types (same
expressive power as our records, but they can sometimes avoid exponential
explosion where we cannot); powerful filter operation.
</p>

</box>

<box title="Related links" link="links">
<link url="http://www.w3.org/XML/"
title="Extensible Markup Language (XML)"> The W3C page on XML. </link>
<link url="http://www.research.avayalabs.com/user/wadler/xml/"
title="XML: Some hyperlinks minus the hype"> By Philip Wadler. </link>
<link url="http://xduce.sourceforge.net/"
title="XDuce"> XDuce home page. </link>
<link url="http://www.cis.upenn.edu/~bcpierce/xtatic/"
title="Xtatic"> The Xtatic Project. </link>
</box>


<meta>
<p>
<a href="comeon.htm">
<img style="border:0;width:88px;height:31px"
     src="img/cducepower3.png" 
     alt="Powered by CDuce"/>
</a>

<a href="http://validator.w3.org/check?uri=http%3A%2F%2Fwww.cduce.org">
<img style="border:0;width:88px;height:31px"
     src="http://www.w3.org/Icons/valid-xhtml10"
     alt="Valid XHTML 1.0!"/>
</a>

<a href="http://jigsaw.w3.org/css-validator/">
<img style="border:0;width:88px;height:31px"
     src="http://jigsaw.w3.org/css-validator/images/vcss" 
     alt="Valid CSS!"/>
</a>

<a href="http://www.ens.fr">
<img style="border:0"
     src="img//symbENSmio.gif"
     alt="ENS" title="ENS"/>
</a>

<a href="http://www.u-psud.fr">
<img style="border:0" 
     src="img//symbP11mio.gif" 
     alt="Paris 11" title="Paris 11"/>
</a>

<a href="http://www.cnrs.fr">
<img style="border:0" 
     src="img//symbCNRSmio.gif" 
     alt="CNRS" title="CNRS"/>
</a>
</p>
<p>
<a href="mailto:Alain.Frisch@ens.fr">Webmaster</a> -
<local href="sitemap">Site map</local>
</p>
</meta>


<page name="img" new="">
<title>Pictures and Logos</title>

<left>
<boxes-toc/>
<p>See also:</p>
<local-links href="index,team,sitemap"/>
</left>

<box title="Pictures" link="pictures">
<section title="The CDuce team (January 2004 - Venice)">
<img src="img/seducers.jpg" alt="The CDuce and XDuce teams"/>
<p>
From left to right:
Véronique Benzaken, 
Haruo Hosoya (pretending to be an X-man),
Cédric Miachon,
Giuseppe Castagna,
Alain Frisch,
Marwan Burelle.
</p>
</section>
<section title="The CDuce and XDuce teams (January 2004 - Venice)">
<img src="img/C+X.jpg" alt="The CDuce and XDuce teams"/>
</section>
<section title="Alain (February 2004 - Hakone)">
<img src="img/frisch_psd_talk.jpg" alt="Alain Frisch"/>
<p>
It's all about hand-waving.
</p>
</section>
<section title="Giuseppe (February 2004 - Hakone)">
<img src="img/beppe_whiteboard.jpg" alt="Giuseppe Castagna"/>
<p>
Beppe cannot stay still for a photo.
</p>
</section>
<section title="Giuseppe (February 2004 - Hakone)">
<img src="img/beppe_whiteboard2.jpg" alt="Giuseppe Castagna"/>
<p>
Beppe cannot stay still for a photo.
</p>
</section>


</box>
<box title="Logos" link="logos">
<p>
Feel free to use the following logos on your websites to make
reference to CDuce.
</p>
<p>
<img src="img/cduce_logo.jpg" alt="CDuce banner"/>
<br/>
<img src="img/cducepower.jpg" alt="Powered by CDuce"/>
<br/>
<img src="img/cducepower2.jpg" alt="Powered by CDuce"/>
</p>
</box>
</page>

</page>