Removing the datatype declaration of "order" allows the standard General.order
to be used. Thus we can use Int.compare and String.compare instead of the
slower home-grown versions.
Itrev = Main +
consts itrev :: 'a list => 'a list => 'a list
primrec
"itrev [] ys = ys"
"itrev (x#xs) ys = itrev xs (x#ys)"
end