Added schema comparison table

diff --git a/docbook/relaxng/docbook/howto/howto.css b/docbook/relaxng/docbook/howto/howto.css
index 6253d96b9e8989bb59f3a532514b4360582d1a60..8df1626abb24223f96872dec07fadd6bda019956 100644 (file)
--- a/docbook/relaxng/docbook/howto/howto.css
+++ b/docbook/relaxng/docbook/howto/howto.css
@@ -58,3 +58,6 @@ dl            { margin-left: 3em;
        padding: 1px; 
        font-size: smaller; 
        text-transform: uppercase }
+
+.yes     { color: green; }
+.no      { color: red; }

diff --git a/docbook/relaxng/docbook/howto/howto.xml b/docbook/relaxng/docbook/howto/howto.xml
index 8621d341ee0deac635735446b0d16866a8dfa112..d307f6ecd3730a83e0bfe2c8d53fe4862c87da7e 100644 (file)
--- a/docbook/relaxng/docbook/howto/howto.xml
+++ b/docbook/relaxng/docbook/howto/howto.xml
@@ -1,6 +1,12 @@
 <?xml version="1.0" encoding="utf-8"?>  <!-- -*- nxml -*- -->
 <!DOCTYPE article [
 <!ENTITY version "5.0">
+<!--
+<!ENTITY yes "<phrase role='unicode yes'>✔</phrase>">
+<!ENTITY no "<phrase role='unicode no'>✘</phrase>">
+-->
+<!ENTITY yes "<phrase role='unicode yes'>YES</phrase>">
+<!ENTITY no "<phrase role='unicode no'>NO</phrase>">
 ]>
 <article xmlns="http://docbook.org/ns/docbook"
         xmlns:xl="http://www.w3.org/1999/xlink"
@@ -214,7 +220,8 @@ V5.0. But please note that neither the DTD nor the W3C XML schema are able to
 capture all the constraints of DocBook V5.0. This mean that a
 document that validates against the DTD or XML schema is not necessarily
 valid against the RELAX NG schema and thus may not be a valid
-DocBook V5.0 document.</para>
+DocBook V5.0 document. See <xref linkend="t.schema-comparison"/> for
+summary of constraints that are checked by different schemas.</para>
 
 <para>DTD and W3C XML Schema versions of the DocBook V5.0 grammar are provided
 as a convenience for users who want to use DocBook V5.0 with legacy tools
@@ -228,6 +235,136 @@ constraints DocBook V5.0 uses Schematron.  We recommend that you
 validate your document against both the RELAX NG and
 Schematron schemas.</para>
 
+<table xml:id="t.schema-comparison">
+  <title>Schema Comparison</title>
+  <tgroup cols="6">
+    <colspec colwidth="4*"/>
+    <colspec colwidth="1*" align="center"/>
+    <colspec colwidth="1*" align="center"/>
+    <colspec colwidth="1*" align="center"/>
+    <colspec colwidth="1*" align="center"/>
+    <colspec colwidth="1*" align="center"/>
+    <thead>
+      <row>
+       <entry>Description</entry>
+       <entry>DTD</entry>
+       <entry>W3C XML Schema</entry>
+       <entry>W3C XML Schema + Schematron</entry>
+       <entry>RELAX NG</entry>
+       <entry>RELAX NG + Schematron/NVDL</entry>
+      </row>
+    </thead>
+    <tbody>
+      <row>
+       <entry>Basic document structure</entry>
+       <entry>&yes;</entry>
+       <entry>&yes;</entry>
+       <entry>&yes;</entry>
+       <entry>&yes;</entry>
+       <entry>&yes;</entry>
+      </row>
+      <row>
+       <entry>ID/IDREF datatypes</entry>
+       <entry>&yes;</entry>
+       <entry>&yes;</entry>
+       <entry>&yes;</entry>
+       <entry>&yes;</entry>
+       <entry>&yes;</entry>
+      </row>
+      <row>
+       <entry>Datatypes<footnote>
+         <para>In a very few places RELAX NG specifies datatype
+         like number (mainly for length specifications) or
+         enumeration between <literal>0</literal> and
+         <literal>1</literal>.</para>
+         <para>In general those datatypes can be also supported in
+         W3C XML Schema, but currently this schema is generated
+         from DTD which lacks datatype information.</para>
+       </footnote>
+       </entry>
+       <entry>&no;</entry>
+       <entry>&no;</entry>
+       <entry>&no;</entry>
+       <entry>&yes;</entry>
+       <entry>&yes;</entry>
+      </row>
+      <row>
+       <entry>Co-occurrences<footnote>
+       <para>RELAX NG grammar enforces exclusivity of several
+       elements. For example if you have <tag>title</tag> inside
+       <tag>info</tag> then it is not allowed to have another
+       <tag>title</tag> outside <tag>info</tag>. Similarly,
+       models of HTML and CALS tables are separated and validated
+       properly, where in DTD and WXS only union of both models is
+       available.</para>
+       <para>On other places co-occurrences enforces particular
+       content model based on presence of specific attribute or
+       attribute value.</para>
+       <para>Please also note that in theory co-occurences can be
+       validated using Schematron, but the current DocBook schema
+       uses RELAX NG for these definitions. Schematron can be used
+       only for validation, whereas grammar based schemas like
+       RELAX NG are useful also for other purposes like guided editing.</para>
+       </footnote></entry>
+       <entry>&no;</entry>
+       <entry>&no;</entry>
+       <entry>&no;</entry>
+       <entry>&yes;</entry>
+       <entry>&yes;</entry>
+      </row>
+      <row>
+       <entry>Hooks for MathML and SVG content</entry>
+       <entry>&no;</entry>
+       <entry>&no;</entry>
+       <entry>&no;</entry>
+       <entry>&yes;</entry>
+       <entry>&yes;</entry>
+      </row>
+      <row>
+       <entry>Link type integrity<footnote>
+       <para>Check whether ID/IDREF links are pointing to element
+       of corresponding type. For example that
+       <tag>footnoteref</tag> points to
+       <tag>footnote</tag>.</para></footnote></entry>
+       <entry>&no;</entry>
+       <entry>&no;</entry>
+       <entry>&yes;</entry>
+       <entry>&no;</entry>
+       <entry>&yes;</entry>
+      </row>
+      <row>
+       <entry>Presence of <tag class="attribute">version</tag>
+       attribute on the root element</entry>
+       <entry>&no;</entry>
+       <entry>&no;</entry>
+       <entry>&yes;</entry>
+       <entry>&no;</entry>
+       <entry>&yes;</entry>
+      </row>
+      <row>
+       <entry>Miscellaneous checks<footnote>
+       <para>For example consistency of segmented lists, only one
+       term inside term definition etc.</para></footnote></entry>
+       <entry>&no;</entry>
+       <entry>&no;</entry>
+       <entry>&yes;</entry>
+       <entry>&no;</entry>
+       <entry>&yes;</entry>
+      </row>
+      <row>
+       <entry>Element exclusions<footnote>
+       <para>Prevents improper nesting of elements, like admonition
+       inside admonition.</para></footnote></entry>
+       <entry>&no;</entry>
+       <entry>&no;</entry>
+       <entry>&yes;</entry>
+       <entry>&no;</entry>
+       <entry>&yes;</entry>
+      </row>        
+    </tbody>
+  </tgroup>
+</table>
+
 <section xml:id="schemas">
 <title>Where to get the schemas</title>