Build a new version hopefully near complete and fully documented of the

* doc/libxml2-api.xml doc/parsedecl.py: Build a new version
  hopefully near complete and fully documented of the API in XML
* HTMLtree.c SAX.c debugXML.c error.c globals.c parser.c tree.c
 xmlIO.c xmlmemory.c include/libxml/catalog.h include/libxml/hash.h
 include/libxml/list.h include/libxml/parser.h include/libxml/tree.h
 include/libxml/parserInternals.h include/libxml/valid.hi
 include/libxml/xmlIO.h include/libxml/xmlerror.hi
 include/libxml/xmlmemory.h include/libxml/xmlversion.h.ini
 include/libxml/xpath.h include/libxml/xpathInternals.h:
  Cleaned up the doc comments a lot in the process, the interface
  coverage is now 100%
Daniel
diff --git a/include/libxml/xpathInternals.h b/include/libxml/xpathInternals.h
index 2b53c9f..5d7cd28 100644
--- a/include/libxml/xpathInternals.h
+++ b/include/libxml/xpathInternals.h
@@ -324,7 +324,18 @@
 /*
  * Variable Lookup forwarding
  */
-typedef xmlXPathObjectPtr (*xmlXPathVariableLookupFunc)	(void *ctxt,
+/**
+ * xmlXPathVariableLookupFunc:
+ * @ctxt:  an XPath context
+ * @name:  name of the variable
+ * @ns_uri:  the namespace name hosting this variable
+ *
+ * Prototype for callbacks used to plug variable lookup in the XPath
+ * engine
+ *
+ * Returns the XPath object value or NULL if not found
+ */
+typedef xmlXPathObjectPtr (*xmlXPathVariableLookupFunc) (void *ctxt,
 					 const xmlChar *name,
 					 const xmlChar *ns_uri);
 
@@ -335,6 +346,17 @@
 /*
  * Function Lookup forwarding
  */
+/**
+ * xmlXPathFuncLookupFunc:
+ * @ctxt:  an XPath context
+ * @name:  name of the function
+ * @ns_uri:  the namespace name hosting this function
+ *
+ * Prototype for callbacks used to plug function lookup in the XPath
+ * engine
+ *
+ * Returns the XPath function or NULL if not found
+ */
 typedef xmlXPathFunction (*xmlXPathFuncLookupFunc) (void *ctxt,
 					 const xmlChar *name,
 					 const xmlChar *ns_uri);