- Datatype package now also supports arbitrarily branching datatypes
(using function types).
- Added new simplification procedure for proving distinctness of
constructors.
- dtK is now a reference.
Sep2 = List +
consts sep :: "'a * 'a list => 'a list"
recdef sep "measure (%(a,xs). length xs)"
"sep(a, x#y#zs) = x # a # sep(a,y#zs)"
"sep(a, xs) = xs"
end