[perl-xml-cvs] CVS: perl-xml-faq perl-xml-faq.xml,1.2,1.3

[Grant M. <gr...@us...>]

Update of /cvsroot/perl-xml/perl-xml-faq
In directory usw-pr-cvs1:/tmp/cvs-serv24884

Modified Files:
	perl-xml-faq.xml 
Log Message:
- more stuff on validation

Index: perl-xml-faq.xml
===================================================================
RCS file: /cvsroot/perl-xml/perl-xml-faq/perl-xml-faq.xml,v
retrieving revision 1.2
retrieving revision 1.3
diff -u -d -r1.2 -r1.3
--- perl-xml-faq.xml	2 Apr 2002 21:42:35 -0000	1.2
+++ perl-xml-faq.xml	4 Apr 2002 21:35:22 -0000	1.3
@@ -1274,9 +1274,51 @@
       you would use <classname>XML::Parser</classname>.  It works the same
       way except that it performs DTD validation.</para>
 
-<!--
-FIXME: XML::Checker sample code
--->
+      <para>Here's a short example to get you going.  Here's a DTD saved
+      in a file called <filename>/opt/xml/xcard.dtd</filename>:</para>
+
+      <programlisting><![CDATA[
+<!ELEMENT xcard (firstname,lastname,email?)>
+<!ELEMENT firstname (#PCDATA)>
+<!ELEMENT lastname (#PCDATA)>
+<!ELEMENT email (#PCDATA)>
+	]]></programlisting>
+
+      <para>Here's an XML document that refer's to the DTD:</para>
+
+      <programlisting><![CDATA[
+<?xml version="1.0" ?>
+<!DOCTYPE xcard SYSTEM "file:/opt/xml/xcard.dtd" >
+<xcard>
+<firstname>Joe</firstname>
+<lastname>Bloggs</lastname>
+<email>jo...@bl...</email>
+</xcard> 
+	]]></programlisting>
+
+      <para>And here's a code snippet to validate the document:</para>
+
+      <programlisting><![CDATA[
+use XML::Checker::Parser;
+
+my $xp = new XML::Checker::Parser ( Handlers => { } );
+
+eval {
+  $xp->parsefile($xml_file);
+};
+if ($@) {
+  # ... your error handling code here ...
+  print "$xml_file failed validation!\n";
+  die "$@";
+}
+print "$xml_file passed validation\n";
+	]]></programlisting>
+
+      <para>You can play around with adding and removing elements from the
+      document to get a idea of what happens when validation errors
+      occur.  You'll also want to refer to the documentation for the
+      'SkipExternalDTD' option for more robust handling of external
+      DTDs.</para>
 
     </answer>
   </qandaentry>
@@ -1295,6 +1337,12 @@
 $parser->validation(1);
 	]]></programlisting>
 
+      <para>Validation using <classname>XML::LibXML</classname> is much faster
+      than with <classname>XML::Checker</classname> but if you want to know why
+      a document fails validation you'll find that
+      <classname>XML::LibXML</classname>'s diagnostic messages are not as
+      helpful.</para>
+
     </answer>
   </qandaentry>
 
@@ -1308,6 +1356,21 @@
       url="http://www.xml.com/pub/au/83">an article</ulink> describing how a
       combination of Perl and XPath can provide a quick, lightweight solution
       for validating documents.</para>
+
+    </answer>
+  </qandaentry>
+
+  <qandaentry id="validation_schematron">
+    <question>
+      <para><classname>XML::Schematron</classname></para>
+    </question>
+    <answer>
+
+      <para>Kip has also written the <classname>XML::Schematron</classname>
+      module which can be used with either <classname>XML::XPath</classname> or
+      <classname>XML::Sablotron</classname> to implement validation based on
+      Rick Jelliffe's <ulink
+      url="http://www.ascc.net/xml/resource/schematron/">Schematron</ulink>.</para>
 
     </answer>
   </qandaentry>