lucas - added option to select occurance to rewrite e.g. (occ 4)
lucas - added option to select occurance to rewrite e.g. (occ 4)

MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle