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This element is the local root of the definition of the XForms Model. It is typically found in a non-rendered area of the containing document.
In the following example, the head section in XHTML can contain an XForms Model.
<html xmlns="http://www.w3.org/1999/xhtml" xmlns:xforms="http://www.w3.org/2002/xforms">
<head>
<title>A sample XHTML+XForms document</title>
<xforms:model>
...more XForms elements...
</xforms:model>
</head>
<body>
...
The attribute functions declares any extension functions, as covered in Chapter 11, Extending XForms, that are absolutely necessary for the form to function.
The attribute schema includes a space-separated list of external XML Schema documents to be retrieved and included in the definition of the XForms Model. Additionally, XML Schema definitions may occur inline, with one or more xs:schema elements appearing as children of the model element. As Chapter 6, The XForms User Interface will describe, the datatype associated with a node can have an effect on the user interface presented to the user for populating the node with data.
Since the model element is a target of several kinds of events (see Chapter 7, Actions and Events), XML Events attributes are also permitted in this element.