Changed "code" attribute of concat_map_singleton to "code unfold".
Changed "code" attribute of concat_map_singleton to "code unfold".

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