Streamlined datatype_codegen function using new datatype_of_case and datatype_of_constr functions.
Streamlined datatype_codegen function using new datatype_of_case
and datatype_of_constr functions.

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