This function takes an RTF document and returns the elements/control codes and groups that makes up its contents.
The RTF document to parse.
repeated exactly once
zero or more rows
Id given by the parser to the element for unique identification (Id:s are given in the same order as the element is encountered in the document).
The text that constitutes the element.
Reference to the elements parent element (if any).
A value of 1 indicates that the element also corresponds to the start of a new group. Any additional element or subgroup inside this group will consider this element as its parent element.