centralized deletion of equations for constructors; corrected misunderstanding what `old functions` are supposed to be
centralized deletion of equations for constructors; corrected misunderstanding what `old functions` are supposed to be

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