Origin for each line in src/example02.red from check-in c1ddb4c814:

c1ddb4c814 2021-03-01    1: u:=(x+y+z)^3;
c1ddb4c814 2021-03-01    2: on factor; u;
c1ddb4c814 2021-03-01    3: df(x^x,x);
c1ddb4c814 2021-03-01    4: int(ws,x);
c1ddb4c814 2021-03-01    5: sin(pi/4);
c1ddb4c814 2021-03-01    6: sin(x)^2+cos(x)^2;
c1ddb4c814 2021-03-01    7: trigsimp ws;
c1ddb4c814 2021-03-01    8: v:=sqrt(pi);
c1ddb4c814 2021-03-01    9: on rounded; v;
c1ddb4c814 2021-03-01   10: precision(24); v;
c1ddb4c814 2021-03-01   11: off rounded;
c1ddb4c814 2021-03-01   12: end;
c1ddb4c814 2021-03-01   13: