--- modules/damieng/clean_xml/loncapa.xsd	2015/05/22 19:50:13	1.15
+++ modules/damieng/clean_xml/loncapa.xsd	2017/01/05 16:55:16	1.19
@@ -1,7 +1,17 @@
-<?xml version="1.0" encoding="UTF-8"?><xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" xml:lang="en">
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+  This schema was created for LON-CAPA.
+  Element documentation often comes from the Mozilla Developer Network.
+  MDN wiki documents are created by Mozilla Contributors and licensed under CC-BY-SA 2.5.
+  Links:
+      https://developer.mozilla.org/en-US/docs/Web/HTML/Element
+      https://developer.mozilla.org/en-US/docs/MDN/About$history
+      http://creativecommons.org/licenses/by-sa/2.5/
+-->
+<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" xml:lang="en">
   <xs:annotation>
     <xs:documentation>
-      XML schema for LON-CAPA 2 documents.
+      XML schema for LON-CAPA documents.
     </xs:documentation>
   </xs:annotation>
   
@@ -137,6 +147,7 @@
     </xs:annotation>
     <xs:complexType mixed="true">
       <xs:choice maxOccurs="unbounded" minOccurs="0">
+        <xs:element ref="head"/>
         <xs:group ref="text-with-parts"/>
         <xs:group ref="inserts"/>
         <xs:element ref="allow"/>
@@ -229,7 +240,6 @@
       <xs:element ref="standalone"/>
       <xs:element ref="script"/>
       <xs:element ref="languageblock"/>
-      <xs:element ref="translated"/>
       <xs:element ref="window"/>
       <xs:element ref="windowlink"/>
       <xs:element ref="togglebox"/>
@@ -326,6 +336,7 @@
       <xs:element ref="textline"/>
       <xs:element ref="displayweight"/>
       <xs:element ref="displaystudentphoto"/>
+      <xs:element ref="translated"/>
       
       <xs:element ref="span"/>
       <xs:element ref="a"/>
@@ -2240,6 +2251,7 @@
     <xs:annotation>
       <xs:documentation>
         Query for a chemical reaction.
+        An internal textline element is necessary for the student's response to go in.
       </xs:documentation>
     </xs:annotation>
     <xs:complexType mixed="true">
@@ -2252,11 +2264,24 @@
         <xs:group ref="text-only"/>
       </xs:choice>
       <xs:attributeGroup ref="response-identification"/>
-      <xs:attribute name="answer" type="xs:string" use="required"/>
+      <xs:attribute name="answer" type="xs:string" use="required">
+        <xs:annotation>
+          <xs:documentation>
+            The correct answer.
+            Chemical reactions use the following syntax:
+            - Reactants are separated from products by '-&gt;'.
+            - Individual reactants and products are separated by ' +' (leading space is obligatory).
+            - Numbers preceding the first symbol of a chemical specie are considered to be stoichiometric coefficients.
+            - Numbers appearing after the first symbol of a chemical specie are considered to be subscripts.
+            - Superscripts are initialized by '^' and terminated by a space.
+            - Ionic charges are superscripts composed of a number followed by a sign (i.e. '^2+').
+          </xs:documentation>
+        </xs:annotation>
+      </xs:attribute>
       <xs:attribute name="initial" type="xs:string">
         <xs:annotation>
           <xs:documentation>
-            Initial Reaction
+            Initial reaction displayed to students. See the answer attribute for the syntax.
           </xs:documentation>
         </xs:annotation>
       </xs:attribute>
@@ -2499,6 +2524,14 @@
       </xs:documentation>
     </xs:annotation>
     <xs:complexType>
+      <xs:attribute name="id" type="xs:string">
+        <xs:annotation>
+          <xs:documentation>
+            Id that will be part of the HTML input element id.
+            This can be used to get a reference to the input element in Javascript.
+          </xs:documentation>
+        </xs:annotation>
+      </xs:attribute>
       <xs:attribute default="20" name="size" type="int-or-perl">
         <xs:annotation>
           <xs:documentation>
@@ -5107,13 +5140,19 @@
           </xs:documentation>
         </xs:annotation>
       </xs:attribute>
-      <xs:attribute default="reaction" name="options">
+      <xs:attribute name="options">
+        <xs:annotation>
+          <xs:documentation>
+            Comma-separated list of options:
+            reaction: is a reaction (note: setting this option is only useful for the editor, it does not change the resulting image)
+            border: draws a border around the image
+          </xs:documentation>
+        </xs:annotation>
         <xs:simpleType>
           <xs:union memberTypes="perl">
             <xs:simpleType>
               <xs:restriction base="xs:string">
-                <xs:enumeration value="reaction"/>
-                <xs:enumeration value="border"/>
+                <xs:pattern value="reaction|border|reaction\s*,\s*border|border\s*,\s*reaction"/>
               </xs:restriction>
             </xs:simpleType>
           </xs:union>
@@ -5469,6 +5508,7 @@
       <xs:sequence>
         <xs:element ref="head"/>
         <xs:element ref="body"/>
+        <xs:element ref="allow" minOccurs="0" maxOccurs="unbounded"/>
       </xs:sequence>
       <xs:attributeGroup ref="i18n"/>
       <xs:attribute name="id" type="xs:ID"/>
@@ -5479,13 +5519,7 @@
       <xs:choice maxOccurs="unbounded" minOccurs="0">
         <xs:element ref="script"/>
         <xs:element ref="style"/>
-        <xs:element name="meta" type="htmlMeta">
-          <xs:annotation>
-            <xs:documentation>
-              generic metainformation
-            </xs:documentation>
-          </xs:annotation>
-        </xs:element>
+        <xs:element name="meta" type="htmlMeta"/>
         <xs:element ref="link"/>
         <xs:element ref="import"/>
       </xs:choice>
@@ -5500,7 +5534,7 @@
     <xs:complexType>
       <xs:sequence>
         <xs:group ref="head.misc"/>
-        <xs:choice>
+        <xs:choice minOccurs="0">
           <xs:sequence>
             <xs:element ref="title"/>
             <xs:group ref="head.misc"/>
@@ -5512,8 +5546,10 @@
           <xs:sequence>
             <xs:element ref="base"/>
             <xs:group ref="head.misc"/>
-            <xs:element ref="title"/>
-            <xs:group ref="head.misc"/>
+            <xs:sequence minOccurs="0">
+              <xs:element ref="title"/>
+              <xs:group ref="head.misc"/>
+            </xs:sequence>
           </xs:sequence>
         </xs:choice>
       </xs:sequence>
@@ -5546,7 +5582,7 @@
   <xs:element name="base">
     <xs:annotation>
       <xs:documentation>
-        Document base URI
+        The HTML Base Element (&lt;base&gt;) specifies the base URL to use for all relative URLs contained within a document. There can be only one &lt;base&gt; element in a document.
       </xs:documentation>
     </xs:annotation>
     <xs:complexType>
@@ -5555,6 +5591,17 @@
     </xs:complexType>
   </xs:element>
   <xs:complexType name="htmlMeta">
+    <xs:annotation>
+      <xs:documentation>
+        The HTML Meta Element (&lt;meta&gt;) represents any metadata information that cannot be represented by one of the other HTML meta-related elements (&lt;base&gt;, &lt;link&gt;, &lt;script&gt;, &lt;style&gt; or &lt;title&gt;).
+
+        Depending on the attributes set, the kind of metadata can be one of the following:
+        - If name is set, it is document-level metadata, applying to the whole page.
+        - If http-equiv is set, it is a pragma directive, i.e. information normally given by the web server about how the - web page should be served.
+        - If charset is set, it is a charset declaration, i.e. the charset used for the serialized form of the webpage. HTML5
+        - if the itemprop is set, a user-defined metadata, transparent for the user-agent as the semantics of the metadata is user-specific.
+      </xs:documentation>
+    </xs:annotation>
     <xs:attributeGroup ref="i18n"/>
     <xs:attribute name="id" type="xs:ID"/>
     <xs:attribute name="http-equiv">
@@ -5767,7 +5814,7 @@
   <xs:element name="body">
     <xs:annotation>
       <xs:documentation>
-        The HTML &lt;body&gt; element represents the content of an HTML document. There is only one &lt;body&gt; element in a document.
+        The HTML Body Element (&lt;body&gt;) represents the content of an HTML document. There can be only one &lt;body&gt; element in a document.
       </xs:documentation>
     </xs:annotation>
     <xs:complexType>
@@ -5827,6 +5874,7 @@
       <xs:choice maxOccurs="unbounded" minOccurs="0">
         <xs:group ref="text-only"/>
       </xs:choice>
+      <xs:attributeGroup ref="coreattrs"/>
     </xs:complexType>
   </xs:element>
   <xs:element name="footer">
@@ -5841,6 +5889,7 @@
       <xs:choice maxOccurs="unbounded" minOccurs="0">
         <xs:group ref="text-only"/>
       </xs:choice>
+      <xs:attributeGroup ref="coreattrs"/>
     </xs:complexType>
   </xs:element>
   <xs:element name="aside">
@@ -5853,6 +5902,7 @@
       <xs:choice maxOccurs="unbounded" minOccurs="0">
         <xs:group ref="text-only"/>
       </xs:choice>
+      <xs:attributeGroup ref="coreattrs"/>
     </xs:complexType>
   </xs:element>
   <xs:element name="h1" type="headerContent">
@@ -6007,7 +6057,9 @@
   <xs:complexType name="ul-base">
     <xs:annotation>
       <xs:documentation>
-        Unordered list
+        The HTML unordered list element (&lt;ul&gt;) represents an unordered list of items, namely a collection of items that do not have a numerical ordering, and their order in the list is meaningless. Typically, unordered-list items are displayed with a bullet, which can be of several forms, like a dot, a circle or a squared. The bullet style is not defined in the HTML description of the page, but in its associated CSS, using the list-style-type property.
+        
+        There is no limitation to the depth and imbrication of lists defined with the &lt;ol&gt; and &lt;ul&gt; elements.
       </xs:documentation>
     </xs:annotation>
     <xs:attributeGroup ref="coreattrs"/>
@@ -6057,7 +6109,9 @@
   <xs:complexType name="ol-base">
     <xs:annotation>
       <xs:documentation>
-        Ordered list
+        The HTML &lt;ol&gt; Element (or HTML Ordered List Element) represents an ordered list of items. Typically, ordered-list items are displayed with a preceding numbering, which can be of any form, like numerals, letters or Romans numerals or even simple bullets. This numbered style is not defined in the HTML description of the page, but in its associated CSS, using the list-style-type property.
+        
+        There is no limitation to the depth and overlap of lists defined with the &lt;ol&gt; and &lt;ul&gt; elements.
       </xs:documentation>
     </xs:annotation>
     <xs:attributeGroup ref="coreattrs"/>
@@ -6108,7 +6162,7 @@
   <xs:complexType mixed="true" name="li-base">
     <xs:annotation>
       <xs:documentation>
-        List item
+        The HTML List Item Element (&lt;li&gt;) is used to represent an item in a list. It must be contained in a parent element: an ordered list (&lt;ol&gt;), an unordered list (&lt;ul&gt;), or a menu (&lt;menu&gt;). In menus and unordered lists, list items are usually displayed using bullet points. In ordered lists, they are usually displayed with an ascending counter on the left, such as a number or letter.
       </xs:documentation>
     </xs:annotation>
     <xs:attributeGroup ref="coreattrs"/>
@@ -6643,7 +6697,7 @@
   <xs:element name="span">
     <xs:annotation>
       <xs:documentation>
-        Inline style
+        The HTML &lt;span&gt; element is a generic inline container for phrasing content, which does not inherently represent anything. It can be used to group elements for styling purposes (using the class or id attributes), or because they share attribute values, such as lang. It should be used only when no other semantic element is appropriate. &lt;span&gt; is very much like a &lt;div&gt; element, but &lt;div&gt; is a block-level element whereas a &lt;span&gt; is an inline element.
       </xs:documentation>
     </xs:annotation>
     <xs:complexType mixed="true">
@@ -6772,14 +6826,14 @@
   <xs:element name="em" type="inlineBaseType">
     <xs:annotation>
       <xs:documentation>
-        Emphasis
+        The HTML Emphasis Element (&lt;em&gt;) marks text that has stress emphasis. The &lt;em&gt; element can be nested, with each level of nesting indicating a greater degree of emphasis.
       </xs:documentation>
     </xs:annotation>
   </xs:element>
   <xs:element name="strong" type="inlineBaseType">
     <xs:annotation>
       <xs:documentation>
-        Strong emphasis
+        The HTML Strong Element (&lt;strong&gt;) gives text strong importance, and is typically displayed in bold.
       </xs:documentation>
     </xs:annotation>
   </xs:element>
@@ -6811,12 +6865,18 @@
       </xs:documentation>
     </xs:annotation>
   </xs:element>
-  <xs:element name="pre" type="inlineBaseType">
+  <xs:element name="pre">
     <xs:annotation>
       <xs:documentation>
         The HTML &lt;pre&gt; Element (or HTML Preformatted Text) represents preformatted text. Text within this element is typically displayed in a non-proportional font exactly as it is laid out in the file. Whitespaces inside this element are displayed as typed.
       </xs:documentation>
     </xs:annotation>
+    <xs:complexType mixed="true">
+      <xs:choice maxOccurs="unbounded" minOccurs="0">
+        <xs:group ref="inlines"/>
+      </xs:choice>
+      <xs:attribute fixed="preserve" ref="xml:space"/>
+    </xs:complexType>
   </xs:element>
   <xs:element name="code" type="inlineBaseType">
     <xs:annotation>
@@ -7143,6 +7203,7 @@
           <xs:element minOccurs="0" ref="figcaption"/>
         </xs:sequence>
       </xs:choice>
+      <xs:attributeGroup ref="coreattrs"/>
     </xs:complexType>
   </xs:element>
   <xs:element name="figcaption">
@@ -7259,7 +7320,7 @@
   <xs:element name="param">
     <xs:annotation>
       <xs:documentation>
-        param is used to supply a named property value
+        The HTML &lt;param&gt; element is used to supply a named property value.
       </xs:documentation>
     </xs:annotation>
     <xs:complexType>
@@ -7668,14 +7729,32 @@
     <xs:complexType mixed="true">
       <xs:complexContent>
         <xs:extension base="inlineBaseType">
-          <xs:attribute name="for" type="xs:IDREF"/>
+          <xs:attribute name="for" type="xs:IDREF">
+            <xs:annotation>
+              <xs:documentation>
+                The ID of a labelable form-related element in the same document as the label element. The first such element in the document with an ID matching the value of the for attribute is the labeled control for this label element. 
+              </xs:documentation>
+            </xs:annotation>
+          </xs:attribute>
           <xs:attribute name="accesskey">
+            <xs:annotation>
+              <xs:documentation>
+                A shortcut key to access this element from the keyboard.
+              </xs:documentation>
+            </xs:annotation>
             <xs:simpleType>
               <xs:restriction base="xs:string">
                 <xs:length fixed="true" value="1"/>
               </xs:restriction>
             </xs:simpleType>
           </xs:attribute>
+          <xs:attribute name="form" type="xs:IDREF">
+            <xs:annotation>
+              <xs:documentation>
+                The form element that the label element is associated with (its form owner). If specified, the value of the attribute must be the ID of a &lt;form&gt; element in the same document. This attribute enables you to place label elements anywhere within a document, not just as descendants of their form elements.
+              </xs:documentation>
+            </xs:annotation>
+          </xs:attribute>
           <xs:attribute name="onfocus" type="xs:string"/>
           <xs:attribute name="onblur" type="xs:string"/>
         </xs:extension>