viewcvs.cgi/web/index.xml

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

<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/cducepower2.jpg" alt="Powered by CDuce"/></p>
</left>

<box title="Latest News" link="news">

<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">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,
our <local href="papers">technical papers</local>.
</p>

<section title="Getting more information">

<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. We also have some 
<local href="examples">larger examples</local>. </p>

<p>We are planning to distribute a stable release in the next
few weeks. To help us prepare this release, you can download a
<local href="download">beta version</local>, and send your comments.
</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. 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, partial support of <a href="http://www.w3.org/TR/xmlschema-1/">XML Schema</a> validation is
in alpha testing (and undocumented) while queries are being
implemented.
</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>


</box>

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

<p>Our plans concerning the design of the core language
include:</p>
<ul>
 <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>
</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">
<ul>
<li> <link url="http://www.w3.org/XML/"
title="Extensible Markup Language (XML)"> The W3C page on XML. </link>
</li>
<li> <link url="http://www.research.avayalabs.com/user/wadler/xml/"
title="XML: Some hyperlinks minus the hype"> By Philip Wadler. </link>
</li>
<li> <link url="http://xduce.sourceforge.net/"
title="XDuce"> XDuce home page. </link> </li>
</ul> </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>
1	abate	253	<?xml version="1.0" encoding="ISO-8859-1" standalone="yes"?>
2	abate	341	<page name="index">
3	abate	253
4	abate	350	<title>Home page</title>
5	abate	253	<banner>
6			<img title="CDuce" src="img/cduce_logo.jpg" width="400" height="206"
7			alt="CDuce"/>
8			</banner>
9
10	abate	341	<left>
11			<p>On this page:</p>
12			<boxes-toc/>
13			<p>Under this page:</p>
14			<pages-toc/>
15			</left>
16	abate	253
17	abate	341	<external href="/cgi-bin/cduce" title="Online demo" name="proto"/>
18	abate	437	<include file="download.xml"/>
19	abate	341	<include file="bench.xml"/>
20			<include file="papers.xml"/>
21	abate	681	<include file="documentation.xml"/>
22	abate	341	<include file="examples.xml"/>
23	abate	647	<include file="hacking.xml"/>
24	abate	598	<include file="mailing.xml"/>
25	abate	649	<include file="team.xml"/>
26	abate	341	<include file="sitemap.xml"/>
27	abate	253
28	abate	576
29	abate	341	<left>
30	abate	255
31	abate	253	<p> CDuce ("seduce") is a new typed functional language with
32	abate	258	innovative features.</p>
33	abate	253
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	abate	258	<a href="http://www.w3.org/XML/Schema">XML Schema</a>.
43			XML types play a central role in CDuce.
44			</p>
45	abate	253
46	abate	341	</left>
47	abate	253
48	abate	341	<left>
49	abate	305	<p> All pages of this site were automatically generated from an XML description of
50	abate	347	the content by <a href="examples.html#site">the following CDuce program</a>.
51	abate	267	</p><p>
52	abate	253	<img src="img/cducepower2.jpg" alt="Powered by CDuce"/></p>
53	abate	341	</left>
54	abate	253
55	abate	674	<box title="Latest News" link="news">
56	abate	253
57	abate	676	<section title="2003, September 23rd, Wednesday: Volunteers sought.">
58	abate	674	<p>
59	abate	676	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
60	abate	674	us.
61			</p>
62			<br/>
63			</section>
64
65
66			<section title="2003, August 16th, Saturday: Version 0.1.1 released.">
67			<p>
68			This version has several bug-fixes and encodes reference types. You can now use
69	abate	676	<code>:=</code> and <code>;</code>. It is available at the <a href="download">usual place</a>. Try this
70	abate	674	<a href="http://www.cduce.org/cgi-bin/cduce?example=reference">code</a> on
71			the on-line demo for an example on how to use them, and refer to the
72	abate	676	<a href="manual_expressions.html#ref">manual pages</a> for more
73	abate	674	information.
74			</p>
75			<br/>
76			</section>
77			</box>
78
79
80	abate	258	<box title="What is CDuce ?" link="whatis">
81	abate	253
82	abate	258	<p> <b>CDuce</b> is modern programming language, adapted to the
83	abate	674	manipulation of XML documents. It is developed by the <a
84	abate	258	href="http://www.di.ens.fr/~castagna/EQUIPE"><b>Languages</b></a>
85			group of ENS in Paris and the <a
86			href="http://www.lri.fr/bd"><b>Databases</b></a> group of LRI in
87			Orsay, two <a href="http://www.cnrs.fr">CNRS</a> labs.
88	abate	347	See also the <local href="team">CDuce team</local> page,
89			our <local href="papers">technical papers</local>.
90	abate	258	</p>
91
92	abate	591	<section title="Getting more information">
93
94			<p>
95	abate	598	If you want more information about CDuce you can send a mail to
96			<tt>info_at_cduce.org</tt> (replace <tt>_at_</tt> with <tt>@</tt>), or
97			to the most appropriate <a href="mailing.html">CDuce mailing list</a>.
98	abate	591	</p>
99
100			</section>
101
102	abate	253	<section title="Online running prototype">
103	abate	437	<p> To get a feeling of CDuce,
104	abate	674	you can play with the <local href="proto">on-line prototype</local>,
105	abate	437	try the examples and modify them. We also have some
106			<local href="examples">larger examples</local>. </p>
107	abate	253
108	abate	562	<p>We are planning to distribute a stable release in the next
109			few weeks. To help us prepare this release, you can download a
110			<local href="download">beta version</local>, and send your comments.
111	abate	437	</p>
112
113	abate	258	</section>
114	abate	253	</box>
115
116	abate	341	<box title="Design and features" link="design">
117	abate	258	<p> Our point of view and our guideline for the design of CDuce is
118			that a programming language for XML should take XML types (
119	abate	545	DTD, XML Schema, Relax-NG, ...) seriously. The benefit are the following:</p>
120	abate	253
121	abate	258	<ul>
122			<li> <b>static verifications</b>
123	abate	625	(e.g.: ensure that a transformation produces a valid document
124			<footnote>
125
126			Valid with respect to validity constraints
127			that can be expressed by the type system (thus typically excluding
128			constraints like <a
129			href="http://www.w3.org/TR/REC-xml#sec-attribute-types">ID</a> and
130			<a href="http://www.w3.org/TR/REC-xml#sec-attribute-types">IDREF</a>).
131
132			</footnote>);</li>
133	abate	258	<li> in particular, we aim at <b>smooth and safe</b> compositions
134			of XML transformations, and incremental programming;</li>
135			<li> static <b>optimizations</b> and <b>efficient execution model</b>
136			(knowing the type of a document is crucial to extract information
137			efficiently).</li>
138	abate	253	</ul>
139
140	abate	258	<p>
141	abate	642	Some features particular to CDuce:
142	abate	258	</p>
143	abate	253	<ul>
144	abate	258	<li> XML objects can be manipulated as first-class citizen values:
145			elements, sequences, tags, characters and strings, attribute
146			sets; sequences of XML elements can be specified by
147			<b>regular expressions</b>, which also apply to
148			characters strings; </li>
149			<li> functions themselves are <b>first-class</b> values, they
150			can be manipulated, stored in data structure, returned by
151			a function,...</li>
152			<li> a powerful <b>pattern matching</b> operation can perform
153			complex extractions from sequences of XML elements; </li>
154			<li> a rich <b>type algebra</b>, with recursive types and arbitrary
155			boolean combinations (union, intersection, complement) allows
156			precise definitions of data structures and XML types;
157			<b>general purpose types</b> and types constructors are taken seriously
158			(products, extensible records, arbitrary precision integers with interval
159			constraints, Unicode characters);</li>
160			<li> <b>polymorphism</b> through a natural notion of <b>subtyping</b>,
161			and <b>overloaded functions</b> with dynamic dispatch; </li>
162			<li> an highly-effective <b>type-driven compilation schema</b>. </li>
163			</ul>
164	abate	253
165	abate	565	<p>CDuce is fast, functional,
166			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>,
167			<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
168			in alpha testing (and undocumented) while queries are being
169			implemented.
170			</p>
171
172	abate	258	<p>
173	abate	347	<local href="bench">Preliminary benchmarks</local> suggest that despite the
174	abate	300	overhead for static type verification, a CDuce
175	abate	258	program can run faster (30% to 60%) than an equivalent XSLT
176			style-sheet (we performed benchmarks with
177			the xsltproc tools from the Gnome libxslt library).
178			</p>
179	abate	616
180	abate	625
181	abate	258	</box>
182	abate	253
183	abate	258	<box title="Research directions" link="research">
184	abate	253
185	abate	258	<p>Our plans concerning the design of the core language
186			include:</p>
187			<ul>
188			<li>a module system to support incremental programming;</li>
189			<li>parametric polymorphism;</li>
190			<li>XML-friendly primitives, to mimic XSLT transformations.</li>
191	abate	253	</ul>
192
193	abate	258	<p>
194			Apart from the core language design and implementation,
195			our research projects include:
196			</p>
197	abate	253	<ul>
198	abate	258	<li> integration of a <b>query sub-language</b> into CDuce, using
199			types as a primary optimization strategy for request evaluation;</li>
200			<li> study of <b>security</b> (confidentiality, ...) properties in the
201			setting of XML transformations.</li>
202	abate	253	</ul>
203
204	abate	258	<p>
205	abate	347	We wrote several <local href="papers">technical papers</local> about
206	abate	258	the language design and its theoretical foundations.
207			</p>
208	abate	253	</box>
209
210	abate	258	<box title="XDuce and CDuce" link="xduce">
211			<p>
212	abate	253
213	abate	258	The starting point of our work on CDuce was the
214	abate	674	<a href="http://xduce.sourceforge.net/">XDuce</a> language developed
215	abate	258	at the UPenn DB group. Many of CDuce features originate from XDuce.
216			Some of our achievements:
217	abate	253
218	abate	258	</p>
219			<ul>
220			<li>integration of first-class and overloaded functions, arbitrary boolean
221			connectives, and extensible (or not) records, to the semantic
222			definition of subtyping;</li>
223			<li>a subtyping algorithm without backtracking;</li>
224			<li>extending pattern matching to capture non consecutive
225			subsequences; removing tail condition for exact matching
226			(they arrived independently to another solution);</li>
227			<li>efficient evaluation model that takes profit of static type information;</li>
228	abate	253	</ul>
229	abate	258	<p>
230			Of course, the work on XDuce continued during our, and they
231	abate	674	developed nice ideas: mixed attribute-element types (same
232	abate	258	expressive power as our records, but they can sometimes avoid exponential
233			explosion where we cannot); powerful filter operation.
234			</p>
235	abate	614
236	abate	253	</box>
237
238			<box title="Related links" link="links">
239			<ul>
240	abate	352	<li> <link url="http://www.w3.org/XML/"
241			title="Extensible Markup Language (XML)"> The W3C page on XML. </link>
242			</li>
243	abate	253	<li> <link url="http://www.research.avayalabs.com/user/wadler/xml/"
244			title="XML: Some hyperlinks minus the hype"> By Philip Wadler. </link>
245	abate	352	</li>
246			<li> <link url="http://xduce.sourceforge.net/"
247			title="XDuce"> XDuce home page. </link> </li>
248			</ul> </box>
249	abate	253
250
251			<meta>
252			<p>
253			<a href="comeon.htm">
254			<img style="border:0;width:88px;height:31px"
255			src="img/cducepower3.png"
256			alt="Powered by CDuce"/>
257			</a>
258
259	abate	257	<a href="http://validator.w3.org/check?uri=http%3A%2F%2Fwww.cduce.org">
260	abate	253	<img style="border:0;width:88px;height:31px"
261			src="http://www.w3.org/Icons/valid-xhtml10"
262			alt="Valid XHTML 1.0!"/>
263			</a>
264
265	abate	401	<a href="http://jigsaw.w3.org/css-validator/">
266	abate	253	<img style="border:0;width:88px;height:31px"
267			src="http://jigsaw.w3.org/css-validator/images/vcss"
268			alt="Valid CSS!"/>
269			</a>
270
271			<a href="http://www.ens.fr">
272			<img style="border:0"
273			src="img//symbENSmio.gif"
274			alt="ENS" title="ENS"/>
275			</a>
276
277			<a href="http://www.u-psud.fr">
278			<img style="border:0"
279			src="img//symbP11mio.gif"
280			alt="Paris 11" title="Paris 11"/>
281			</a>
282
283			<a href="http://www.cnrs.fr">
284			<img style="border:0"
285			src="img//symbCNRSmio.gif"
286			alt="CNRS" title="CNRS"/>
287			</a>
288			</p>
289			<p>
290	abate	255	<a href="mailto:Alain.Frisch@ens.fr">Webmaster</a> -
291	abate	347	<local href="sitemap">Site map</local>
292	abate	253	</p>
293			</meta>
294
295			</page>