| 1 |
<?xml version="1.0" encoding="ISO-8859-1" standalone="yes"?>
|
| 2 |
<page name="index">
|
| 3 |
|
| 4 |
<title>Home page</title>
|
| 5 |
<banner>
|
| 6 |
<img title="CDuce" src="img/cduce_logo.jpg" width="400" height="206"
|
| 7 |
alt="CDuce"/>
|
| 8 |
</banner>
|
| 9 |
|
| 10 |
<left>
|
| 11 |
<p>On this page:</p>
|
| 12 |
<boxes-toc/>
|
| 13 |
<p>Under this page:</p>
|
| 14 |
<pages-toc/>
|
| 15 |
</left>
|
| 16 |
|
| 17 |
<external href="/cgi-bin/cduce" title="Online demo" name="proto"/>
|
| 18 |
<include file="download.xml"/>
|
| 19 |
<include file="bench.xml"/>
|
| 20 |
<include file="papers.xml"/>
|
| 21 |
<include file="documentation.xml"/>
|
| 22 |
<include file="examples.xml"/>
|
| 23 |
<include file="hacking.xml"/>
|
| 24 |
<include file="mailing.xml"/>
|
| 25 |
<include file="team.xml"/>
|
| 26 |
<include file="sitemap.xml"/>
|
| 27 |
|
| 28 |
|
| 29 |
<left>
|
| 30 |
|
| 31 |
<p> CDuce ("seduce") is a new typed functional language with
|
| 32 |
innovative features.</p>
|
| 33 |
|
| 34 |
<p> Although CDuce is a general programming language, it features
|
| 35 |
several characteristics that make it adapted to XML documents
|
| 36 |
manipulation (transformation, extraction of information, creation of
|
| 37 |
documents).
|
| 38 |
<a href="http://www.w3.org/XML/">XML</a> is a syntax to
|
| 39 |
describe tree-like documents (aka semi-structured data), and XML
|
| 40 |
documents often come with a description of their type. The type is
|
| 41 |
expressed in a system like DTD, or
|
| 42 |
<a href="http://www.w3.org/XML/Schema">XML Schema</a>.
|
| 43 |
XML types play a central role in CDuce.
|
| 44 |
</p>
|
| 45 |
|
| 46 |
</left>
|
| 47 |
|
| 48 |
<left>
|
| 49 |
<p> All pages of this site were automatically generated from an XML description of
|
| 50 |
the content by <a href="examples.html#site">the following CDuce program</a>.
|
| 51 |
</p><p>
|
| 52 |
<img src="img/cducepower2.jpg" alt="Powered by CDuce"/></p>
|
| 53 |
</left>
|
| 54 |
|
| 55 |
<box title="Latest News" link="news">
|
| 56 |
<section title="2003, October 26th, Sunday: New addition to papers.">
|
| 57 |
<p>
|
| 58 |
If you want a simple and basic introduction to the theoretical foundations
|
| 59 |
of CDuce, there is a new entry in the <a href="papers.html">papers page</a>: <i>"A Gentle
|
| 60 |
Introduction to Semantic Subtyping"</i>.
|
| 61 |
</p>
|
| 62 |
<br/>
|
| 63 |
</section>
|
| 64 |
|
| 65 |
<section title="2003, October 17th, Friday: CVS publicly available.">
|
| 66 |
<p>
|
| 67 |
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.
|
| 68 |
</p>
|
| 69 |
<br/>
|
| 70 |
</section>
|
| 71 |
|
| 72 |
|
| 73 |
<section title="2003, September 23rd, Wednesday: Volunteers sought.">
|
| 74 |
<p>
|
| 75 |
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
|
| 76 |
us.
|
| 77 |
</p>
|
| 78 |
<br/>
|
| 79 |
</section>
|
| 80 |
|
| 81 |
|
| 82 |
<section title="2003, August 16th, Saturday: Version 0.1.1 released.">
|
| 83 |
<p>
|
| 84 |
This version has several bug-fixes and encodes reference types. You can now use
|
| 85 |
<code>:=</code> and <code>;</code>. It is available at the <a href="download.html">usual place</a>. Try this
|
| 86 |
<a href="http://www.cduce.org/cgi-bin/cduce?example=reference">code</a> on
|
| 87 |
the on-line demo for an example on how to use them, and refer to the
|
| 88 |
<a href="manual_expressions.html#ref">manual pages</a> for more
|
| 89 |
information.
|
| 90 |
</p>
|
| 91 |
<br/>
|
| 92 |
</section>
|
| 93 |
</box>
|
| 94 |
|
| 95 |
|
| 96 |
<box title="What is CDuce ?" link="whatis">
|
| 97 |
|
| 98 |
<p> <b>CDuce</b> is modern programming language, adapted to the
|
| 99 |
manipulation of XML documents. It is developed by the <a
|
| 100 |
href="http://www.di.ens.fr/~castagna/EQUIPE"><b>Languages</b></a>
|
| 101 |
group of ENS in Paris and the <a
|
| 102 |
href="http://www.lri.fr/bd"><b>Databases</b></a> group of LRI in
|
| 103 |
Orsay, two <a href="http://www.cnrs.fr">CNRS</a> labs.
|
| 104 |
See also the <local href="team">CDuce team</local> page,
|
| 105 |
our <local href="papers">technical papers</local>.
|
| 106 |
</p>
|
| 107 |
|
| 108 |
<section title="Getting more information">
|
| 109 |
|
| 110 |
<p>
|
| 111 |
If you want more information about CDuce you can send a mail to
|
| 112 |
<tt>info_at_cduce.org</tt> (replace <tt>_at_</tt> with <tt>@</tt>), or
|
| 113 |
to the most appropriate <a href="mailing.html">CDuce mailing list</a>.
|
| 114 |
</p>
|
| 115 |
|
| 116 |
</section>
|
| 117 |
|
| 118 |
<section title="Online running prototype">
|
| 119 |
<p> To get a feeling of CDuce,
|
| 120 |
you can play with the <local href="proto">on-line prototype</local>,
|
| 121 |
try the examples and modify them. We also have some
|
| 122 |
<local href="examples">larger examples</local>. </p>
|
| 123 |
|
| 124 |
<p>We are planning to distribute a stable release in the next
|
| 125 |
few weeks. To help us prepare this release, you can download a
|
| 126 |
<local href="download">beta version</local>, and send your comments.
|
| 127 |
</p>
|
| 128 |
|
| 129 |
</section>
|
| 130 |
</box>
|
| 131 |
|
| 132 |
<box title="Design and features" link="design">
|
| 133 |
<p> Our point of view and our guideline for the design of CDuce is
|
| 134 |
that a programming language for XML should take XML types (
|
| 135 |
DTD, XML Schema, Relax-NG, ...) seriously. The benefit are the following:</p>
|
| 136 |
|
| 137 |
<ul>
|
| 138 |
<li> <b>static verifications</b>
|
| 139 |
(e.g.: ensure that a transformation produces a valid document
|
| 140 |
<footnote>
|
| 141 |
|
| 142 |
Valid with respect to validity constraints
|
| 143 |
that can be expressed by the type system (thus typically excluding
|
| 144 |
constraints like <a
|
| 145 |
href="http://www.w3.org/TR/REC-xml#sec-attribute-types">ID</a> and
|
| 146 |
<a href="http://www.w3.org/TR/REC-xml#sec-attribute-types">IDREF</a>).
|
| 147 |
|
| 148 |
</footnote>);</li>
|
| 149 |
<li> in particular, we aim at <b>smooth and safe</b> compositions
|
| 150 |
of XML transformations, and incremental programming;</li>
|
| 151 |
<li> static <b>optimizations</b> and <b>efficient execution model</b>
|
| 152 |
(knowing the type of a document is crucial to extract information
|
| 153 |
efficiently).</li>
|
| 154 |
</ul>
|
| 155 |
|
| 156 |
<p>
|
| 157 |
Some features particular to CDuce:
|
| 158 |
</p>
|
| 159 |
<ul>
|
| 160 |
<li> XML objects can be manipulated as first-class citizen values:
|
| 161 |
elements, sequences, tags, characters and strings, attribute
|
| 162 |
sets; sequences of XML elements can be specified by
|
| 163 |
<b>regular expressions</b>, which also apply to
|
| 164 |
characters strings; </li>
|
| 165 |
<li> functions themselves are <b>first-class</b> values, they
|
| 166 |
can be manipulated, stored in data structure, returned by
|
| 167 |
a function,...</li>
|
| 168 |
<li> a powerful <b>pattern matching</b> operation can perform
|
| 169 |
complex extractions from sequences of XML elements; </li>
|
| 170 |
<li> a rich <b>type algebra</b>, with recursive types and arbitrary
|
| 171 |
boolean combinations (union, intersection, complement) allows
|
| 172 |
precise definitions of data structures and XML types;
|
| 173 |
<b>general purpose types</b> and types constructors are taken seriously
|
| 174 |
(products, extensible records, arbitrary precision integers with interval
|
| 175 |
constraints, Unicode characters);</li>
|
| 176 |
<li> <b>polymorphism</b> through a natural notion of <b>subtyping</b>,
|
| 177 |
and <b>overloaded functions</b> with dynamic dispatch; </li>
|
| 178 |
<li> an highly-effective <b>type-driven compilation schema</b>. </li>
|
| 179 |
</ul>
|
| 180 |
|
| 181 |
<p>CDuce is fast, functional,
|
| 182 |
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>,
|
| 183 |
<a href="http://www.w3.org/TR/REC-xml-names/">Namespaces</a> are fully supported, partial support of <a href="http://www.w3.org/TR/xmlschema-1/">XML Schema</a> validation is
|
| 184 |
in alpha testing (and undocumented) while queries are being
|
| 185 |
implemented.
|
| 186 |
</p>
|
| 187 |
|
| 188 |
<p>
|
| 189 |
<local href="bench">Preliminary benchmarks</local> suggest that despite the
|
| 190 |
overhead for static type verification, a CDuce
|
| 191 |
program can run faster (30% to 60%) than an equivalent XSLT
|
| 192 |
style-sheet (we performed benchmarks with
|
| 193 |
the xsltproc tools from the Gnome libxslt library).
|
| 194 |
</p>
|
| 195 |
|
| 196 |
<p>
|
| 197 |
The named CDuce was coined by Francesco Zappa Nardelli.
|
| 198 |
</p>
|
| 199 |
|
| 200 |
</box>
|
| 201 |
|
| 202 |
<box title="Research directions" link="research">
|
| 203 |
|
| 204 |
<p>Our plans concerning the design of the core language
|
| 205 |
include:</p>
|
| 206 |
<ul>
|
| 207 |
<li>interface with other languages and type systems;</li>
|
| 208 |
<li>efficient evaluation strategies, high-level optimizations;</li>
|
| 209 |
<li>a module system to support incremental programming;</li>
|
| 210 |
<li>parametric polymorphism;</li>
|
| 211 |
<li>XML-friendly primitives, to mimic XSLT transformations.</li>
|
| 212 |
</ul>
|
| 213 |
|
| 214 |
<p>
|
| 215 |
Apart from the core language design and implementation,
|
| 216 |
our research projects include:
|
| 217 |
</p>
|
| 218 |
<ul>
|
| 219 |
<li> integration of a <b>query sub-language</b> into CDuce, using
|
| 220 |
types as a primary optimization strategy for request evaluation;</li>
|
| 221 |
<li> study of <b>security</b> (confidentiality, ...) properties in the
|
| 222 |
setting of XML transformations.</li>
|
| 223 |
</ul>
|
| 224 |
|
| 225 |
<p>
|
| 226 |
We wrote several <local href="papers">technical papers</local> about
|
| 227 |
the language design and its theoretical foundations.
|
| 228 |
</p>
|
| 229 |
</box>
|
| 230 |
|
| 231 |
<box title="XDuce and CDuce" link="xduce">
|
| 232 |
<p>
|
| 233 |
|
| 234 |
The starting point of our work on CDuce was the
|
| 235 |
<a href="http://xduce.sourceforge.net/">XDuce</a> language developed
|
| 236 |
at the UPenn DB group. Many of CDuce features originate from XDuce.
|
| 237 |
Some of our achievements:
|
| 238 |
|
| 239 |
</p>
|
| 240 |
<ul>
|
| 241 |
<li>integration of first-class and overloaded functions, arbitrary boolean
|
| 242 |
connectives, and extensible (or not) records, to the semantic
|
| 243 |
definition of subtyping;</li>
|
| 244 |
<li>a subtyping algorithm without backtracking;</li>
|
| 245 |
<li>extending pattern matching to capture non consecutive
|
| 246 |
subsequences; removing tail condition for exact matching
|
| 247 |
(they arrived independently to another solution);</li>
|
| 248 |
<li>efficient evaluation model that takes profit of static type information;</li>
|
| 249 |
</ul>
|
| 250 |
<p>
|
| 251 |
Of course, the work on XDuce continued during our, and they
|
| 252 |
developed nice ideas: mixed attribute-element types (same
|
| 253 |
expressive power as our records, but they can sometimes avoid exponential
|
| 254 |
explosion where we cannot); powerful filter operation.
|
| 255 |
</p>
|
| 256 |
|
| 257 |
</box>
|
| 258 |
|
| 259 |
<box title="Related links" link="links">
|
| 260 |
<ul>
|
| 261 |
<li> <link url="http://www.w3.org/XML/"
|
| 262 |
title="Extensible Markup Language (XML)"> The W3C page on XML. </link>
|
| 263 |
</li>
|
| 264 |
<li> <link url="http://www.research.avayalabs.com/user/wadler/xml/"
|
| 265 |
title="XML: Some hyperlinks minus the hype"> By Philip Wadler. </link>
|
| 266 |
</li>
|
| 267 |
<li> <link url="http://xduce.sourceforge.net/"
|
| 268 |
title="XDuce"> XDuce home page. </link> </li>
|
| 269 |
</ul> </box>
|
| 270 |
|
| 271 |
|
| 272 |
<meta>
|
| 273 |
<p>
|
| 274 |
<a href="comeon.htm">
|
| 275 |
<img style="border:0;width:88px;height:31px"
|
| 276 |
src="img/cducepower3.png"
|
| 277 |
alt="Powered by CDuce"/>
|
| 278 |
</a>
|
| 279 |
|
| 280 |
<a href="http://validator.w3.org/check?uri=http%3A%2F%2Fwww.cduce.org">
|
| 281 |
<img style="border:0;width:88px;height:31px"
|
| 282 |
src="http://www.w3.org/Icons/valid-xhtml10"
|
| 283 |
alt="Valid XHTML 1.0!"/>
|
| 284 |
</a>
|
| 285 |
|
| 286 |
<a href="http://jigsaw.w3.org/css-validator/">
|
| 287 |
<img style="border:0;width:88px;height:31px"
|
| 288 |
src="http://jigsaw.w3.org/css-validator/images/vcss"
|
| 289 |
alt="Valid CSS!"/>
|
| 290 |
</a>
|
| 291 |
|
| 292 |
<a href="http://www.ens.fr">
|
| 293 |
<img style="border:0"
|
| 294 |
src="img//symbENSmio.gif"
|
| 295 |
alt="ENS" title="ENS"/>
|
| 296 |
</a>
|
| 297 |
|
| 298 |
<a href="http://www.u-psud.fr">
|
| 299 |
<img style="border:0"
|
| 300 |
src="img//symbP11mio.gif"
|
| 301 |
alt="Paris 11" title="Paris 11"/>
|
| 302 |
</a>
|
| 303 |
|
| 304 |
<a href="http://www.cnrs.fr">
|
| 305 |
<img style="border:0"
|
| 306 |
src="img//symbCNRSmio.gif"
|
| 307 |
alt="CNRS" title="CNRS"/>
|
| 308 |
</a>
|
| 309 |
</p>
|
| 310 |
<p>
|
| 311 |
<a href="mailto:Alain.Frisch@ens.fr">Webmaster</a> -
|
| 312 |
<local href="sitemap">Site map</local>
|
| 313 |
</p>
|
| 314 |
</meta>
|
| 315 |
|
| 316 |
</page>
|
Parent Directory
| 
Revision Log