Origin for each line in src/example01.red from check-in c1ddb4c814:

c1ddb4c814 2021-03-01 jeff@gridfini: a:=sin (x);
c1ddb4c814 2021-03-01 jeff@gridfini: b:=cos (x);
c1ddb4c814 2021-03-01 jeff@gridfini: c:=a^2+b^2;
c1ddb4c814 2021-03-01 jeff@gridfini: d:=a/b;
c1ddb4c814 2021-03-01 jeff@gridfini: f:=tan (x)-d;
c1ddb4c814 2021-03-01 jeff@gridfini: trigsimp c;
c1ddb4c814 2021-03-01 jeff@gridfini: trigsimp f;
c1ddb4c814 2021-03-01 jeff@gridfini: end;