def isTopNode(elem) :
					return definesNode(elem) and not lib.hasAncestorElement(elem.parentNode, definesNode)
		def isNonExec(elem) :
			return lib.hasAncestorElement(
				elem, lambda x: x.getAttribute("xml:id") == "non-executable" )
		def isNestedNode(elem) :
			return lib.hasAncestorElement(
				elem, lambda x: x.getAttribute("xml:id").find("node.") == 0 )
	def isFamily(node) :
		return lib.hasAncestorElement(
			node, lambda x: x.getAttribute("xml:id") == "family-node-types" )