Origin for each line in src/heron.txt from check-in c1ddb4c814:

c1ddb4c814 2021-03-01    1: a*(b+c*(d+e*(f+g*(h+j*(k+l*(m+n*(o+p*(q+r))))))));
c1ddb4c814 2021-03-01    2: z:=ws;
c1ddb4c814 2021-03-01    3: off factor;
c1ddb4c814 2021-03-01    4: z;
c1ddb4c814 2021-03-01    5: on factor;
c1ddb4c814 2021-03-01    6: z;
c1ddb4c814 2021-03-01    7: end;