ModelNodeSet
 typedef
Value that can be normalized to an array of nodes.
Non-arrays are normalized as follows:
- Node is left as is,
 - TextProxy and 
stringare normalized to Text, - NodeList is normalized to an array containing all nodes that are in that node list,
 - ModelDocumentFragment is normalized to an array containing all of it's children.
 
Arrays are processed item by item like non-array values and flattened to one array. Normalization always results in a flat array of nodes. Consecutive text nodes (or items normalized to text nodes) will be merged if they have same attributes.