Gets a set of attributes applied to a range of text from an Text object, optionally including its 'default' attributes.
a pointer to the Text object to query.
a int indicating the offset from which the attribute search is based.
a int pointer indicating the start of the desired text range.
a int pointer indicating the first character past the desired range.
a GenericSet with attributes defined at the indicated offset, optionally including the 'default' ones.