for functions with only variable patterns, fixrec definitions no longer use Fixrec.return/Fixrec.run
for functions with only variable patterns, fixrec definitions no longer use Fixrec.return/Fixrec.run

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