mirror of
https://gitlab.gnome.org/GNOME/libxml2.git
synced 2025-02-19 09:57:23 +03:00
Added a small DTD related page following the IRC help needed by maciej on the
topic, Daniel
This commit is contained in:
Daniel Veillard
parent
748e45d780
commit
300f7d6d00
@ -1,3 +1,9 @@
|
||||
Fri Nov 24 14:01:44 CET 2000 Daniel Veillard <Daniel.Veillard@w3.org>
|
||||
|
||||
* doc/xmldtd.html doc/xml.html: following a short step by step
|
||||
guidance on IRC to help maciej with DTDs I started a small
|
||||
page on the subject.
|
||||
|
||||
Fri Nov 17 17:28:06 CET 2000 Daniel Veillard <Daniel.Veillard@w3.org>
|
||||
|
||||
* HTMLparser.c: fixed handling of broken charrefs
|
||||
|
||||
@ -1,7 +1,9 @@
|
||||
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
|
||||
"http://www.w3.org/TR/html4/loose.dtd">
|
||||
<html>
|
||||
<head>
|
||||
<title>The XML C library for Gnome</title>
|
||||
<meta name="GENERATOR" content="amaya V4.0">
|
||||
<meta name="GENERATOR" content="amaya V4.1">
|
||||
<meta http-equiv="Content-Type" content="text/html">
|
||||
</head>
|
||||
|
||||
@ -52,6 +54,8 @@ alt="W3C Logo"></a></p>
|
||||
<li><a href="encoding.html">libxml Internationalization support</a></li>
|
||||
<li><a href="xmlio.html">libxml Input/Output interfaces</a></li>
|
||||
<li><a href="xmlmem.html">libxml Memory interfaces</a></li>
|
||||
<li><a href="xmldtd.html">a short introduction about DTDs and
|
||||
libxml</a></li>
|
||||
</ul>
|
||||
|
||||
<h2><a name="Introducti">Introduction</a></h2>
|
||||
@ -1374,6 +1378,6 @@ Gnome CVS base under gnome-xml/example</p>
|
||||
|
||||
<p><a href="mailto:Daniel.Veillard@w3.org">Daniel Veillard</a></p>
|
||||
|
||||
<p>$Id: xml.html,v 1.57 2000/10/25 13:32:38 veillard Exp $</p>
|
||||
<p>$Id: xml.html,v 1.58 2000/11/13 18:22:47 veillard Exp $</p>
|
||||
</body>
|
||||
</html>
|
||||
|
||||
191
doc/xmldtd.html
Normal file
191
doc/xmldtd.html
Normal file
@ -0,0 +1,191 @@
|
||||
<html>
|
||||
<head>
|
||||
<title>Libxml Input/Output handling</title>
|
||||
<meta name="GENERATOR" content="amaya V4.0">
|
||||
<meta http-equiv="Content-Type" content="text/html">
|
||||
</head>
|
||||
|
||||
<body bgcolor="#ffffff">
|
||||
<h1 align="center">Libxml DTD support</h1>
|
||||
|
||||
<p>Location: <a
|
||||
href="http://xmlsoft.org/xmlio.html">http://xmlsoft.org/xmldtd.html</a></p>
|
||||
|
||||
<p>Libxml home page: <a href="http://xmlsoft.org/">http://xmlsoft.org/</a></p>
|
||||
|
||||
<p>Mailing-list archive: <a
|
||||
href="http://xmlsoft.org/messages/">http://xmlsoft.org/messages/</a></p>
|
||||
|
||||
<p>Version: $Revision$</p>
|
||||
|
||||
<p>Table of Content:</p>
|
||||
<ol>
|
||||
<li><a href="#General">General overview</a></li>
|
||||
<li><a href="#definition">The definition</a></li>
|
||||
<li><a href="#Simple">Simple rules</a>
|
||||
<ol>
|
||||
<li><a href="#reference">How to reference a DTD from a document</a></li>
|
||||
<li><a href="#Declaring">Declaring elements</a></li>
|
||||
<li><a href="#Declaring1">Declaring attributes</a></li>
|
||||
</ol>
|
||||
</li>
|
||||
<li><a href="#Some">Some examples</a></li>
|
||||
<li><a href="#validate">How to validate</a></li>
|
||||
<li><a href="#Other">Other resources</a></li>
|
||||
</ol>
|
||||
|
||||
<h2><a name="General">General overview</a></h2>
|
||||
|
||||
<p>DTD is the acronym for Document Type Definition. This is a description of
|
||||
the content for a familly of XML files. This is part of the XML 1.0
|
||||
specification, and alows to describe and check that a given document instance
|
||||
conforms to a set of rules detailing its structure and content. </p>
|
||||
|
||||
<h2><a name="definition">The definition</a></h2>
|
||||
|
||||
<p>The <a href="http://www.w3.org/TR/REC-xml">W3C XML Recommendation</a> (<a
|
||||
href="http://www.xml.com/axml/axml.html">Tim Bray's annotated version of
|
||||
Rev1</a>):</p>
|
||||
<ul>
|
||||
<li><a href="http://www.w3.org/TR/REC-xml#elemdecls">Declaring
|
||||
elements</a></li>
|
||||
<li><a href="http://www.w3.org/TR/REC-xml#attdecls">Declaring
|
||||
attributes</a></li>
|
||||
</ul>
|
||||
|
||||
<p>(unfortunately) all this is inherited from the SGML world, the syntax is
|
||||
ancient...</p>
|
||||
|
||||
<h2><a name="Simple">Simple rules</a></h2>
|
||||
|
||||
<p>Writing DTD can be done in multiple ways, the rules to build them if you
|
||||
need something fixed or something which can evolve over time can be radically
|
||||
different. Really complex DTD like Docbook ones are flexible but quite harder
|
||||
to design. I will just focuse on DTDs for a formats with a fixed simple
|
||||
structure. It is just a set of basic rules, and definitely not exhaustive nor
|
||||
useable for complex DTD design.</p>
|
||||
|
||||
<h3><a name="reference">How to reference a DTD from a document</a>:</h3>
|
||||
|
||||
<p>Assuming the top element of the document is <code>spec</code> and the dtd
|
||||
is placed in the file <code>mydtd</code> in the subdirectory <code>dtds</code>
|
||||
of the directory from where the document were loaded:</p>
|
||||
|
||||
<p><code><!DOCTYPE spec SYSTEM "dtds/mydtd"></code></p>
|
||||
|
||||
<p>Notes: </p>
|
||||
<ul>
|
||||
<li>the system string is actually an URI-Reference (as defined in RFC 2396)
|
||||
so you can use a full URL string indicating the location of your DTD on
|
||||
the Web, this is a really good thing to do if you want others to validate
|
||||
your document</li>
|
||||
<li>it is also possible to associate a <code>PUBLIC</code> identifier (a
|
||||
magic string) so that the DTd is looked up in catalogs on the client side
|
||||
without having to locate it on the web </li>
|
||||
<li>a dtd contains a set of elements and attributes declarations, but they
|
||||
don't define what the root of the document should be. This is explicitely
|
||||
told to the parser/validator as the first element of the
|
||||
<code>DOCTYPE</code> declaration.</li>
|
||||
</ul>
|
||||
|
||||
<h3><a name="Declaring">Declaring elements</a>:</h3>
|
||||
|
||||
<p>The following declares an element <code>spec</code>:</p>
|
||||
|
||||
<p><code><!ELEMENT spec (front, body, back?)></code></p>
|
||||
|
||||
<p>it also expresses that the spec element contains one front, one body and
|
||||
one optionnal back in this order. The declaration of one element of the
|
||||
structure and its content are done in a single declaration. Similary the
|
||||
following declares <code>div1</code> elements:</p>
|
||||
|
||||
<p><code><!ELEMENT div1 (head, (p | list | note)*, div2*)></code></p>
|
||||
|
||||
<p>means div1 contains one head then a series of optional p, lists and notes
|
||||
and then an optional div2. And last but not least an element can contain
|
||||
text:</p>
|
||||
|
||||
<p><code><!ELEMENT b (#PCDATA)></code></p>
|
||||
|
||||
<p><code>b</code> contains text or being of mixed content (text and elements
|
||||
in no particular order):</p>
|
||||
|
||||
<p><code><!ELEMENT p (#PCDATA|a|ul|b|i|em)*></code></p>
|
||||
|
||||
<p> <code>p </code>can contain text or <code>a</code>, <code>ul</code>,
|
||||
<code>b</code>, <code>i </code>or <code>em</code> elements in no particular
|
||||
order.</p>
|
||||
|
||||
<h3><a name="Declaring1">Declaring attributes</a>:</h3>
|
||||
|
||||
<p>again the attributes declaration includes their content definition:</p>
|
||||
|
||||
<p><code><!ATTLIST termdef name CDATA #IMPLIED></code></p>
|
||||
|
||||
<p>means that the element <code>termdef</code> can have a <code>name</code>
|
||||
attribute containing text (<code>CDATA</code>) and which is optionnal
|
||||
(<code>#IMPLIED</code>). The attribute value can also be defined within a
|
||||
set:</p>
|
||||
|
||||
<p><code><!ATTLIST list type (bullets|ordered|glossary)
|
||||
"ordered"></code></p>
|
||||
|
||||
<p>means <code>list</code> element have a <code>type</code> attribute with 3
|
||||
allowed values "bullets", "ordered" or "glossary" and which default to
|
||||
"ordered" if the attribute is not explicitely specified. </p>
|
||||
|
||||
<p>The content type of an attribute can be text (<code>CDATA</code>),
|
||||
anchor/reference/references
|
||||
(<code>ID</code>/<code>IDREF</code>/<code>IDREFS</code>), entity(ies)
|
||||
(<code>ENTITY</code>/<code>ENTITIES</code>) or name(s)
|
||||
(<code>NMTOKEN</code>/<code>NMTOKENS</code>). The following defines that a
|
||||
<code>chapter</code> element can have an optional <code>id</code> attribute of
|
||||
type <code>ID</code>, usable for reference from attribute of type IDREF:</p>
|
||||
|
||||
<p><code><!ATTLIST chapter id ID #IMPLIED></code></p>
|
||||
|
||||
<p>The last value of an attribute definition can be <code>#REQUIRED
|
||||
</code>meaning that the attribute has to be given, <code>#IMPLIED</code>
|
||||
meaning that it is optional, or the default value (possibly prefixed by
|
||||
<code>#FIXED</code> if it is the only allowed).</p>
|
||||
|
||||
<h2><a name="Some">Some examples</a></h2>
|
||||
|
||||
<p>The directory <code>test/valid/dtds/</code> in the libxml distribution
|
||||
contains some complex DTD examples. The <code>test/valid/dia.xml</code>
|
||||
example shows an XML file where the simple DTD is directly included within the
|
||||
document.</p>
|
||||
|
||||
<h2><a name="validate">How to validate</a></h2>
|
||||
|
||||
<p>The simplest is to use the xmllint program comming with libxml. The
|
||||
<code>--valid</code> option turn on validation of the files given as input,
|
||||
for example the following validates a copy of the first revision of the XML
|
||||
1.0 specification:</p>
|
||||
|
||||
<p><code>xmllint --valid --noout test/valid/REC-xml-19980210.xml</code></p>
|
||||
|
||||
<p>the -- noout is used to not output the resulting tree.</p>
|
||||
|
||||
<p>The <code>--dtdvalid dtd</code> allows to validate the document(s) against
|
||||
a given DTD.</p>
|
||||
|
||||
<p>Libxml exports an API to handle DTDs and validation, check the <a
|
||||
href="http://xmlsoft.org/html/gnome-xml-valid.html">associated
|
||||
description</a>.</p>
|
||||
|
||||
<h2><a name="Other">Other resources</a></h2>
|
||||
|
||||
<p>DTDs are as old as SGML. So there may be a number of examples on-line, I
|
||||
will just list one for now, others pointers welcome:</p>
|
||||
<ul>
|
||||
<li><a href="http://www.xml101.com:8081/dtd/">XML-101 DTD</a></li>
|
||||
</ul>
|
||||
|
||||
<p></p>
|
||||
|
||||
<p><a href="mailto:Daniel.Veillard@w3.org">Daniel Veillard</a></p>
|
||||
|
||||
<p>$Id$</p>
|
||||
</body>
|
||||
</html>
|
||||
Loading…
x
Reference in New Issue
Block a user