type S = SNil | SAtom { CString } | SCons { S[], S[] } | SPointer { ?[] }
.into : (S, Type<String>) -> String
== : (S, S) -> Bool
!= : (S, S) -> Bool
< : (S, S) -> Bool
<= : (S, S) -> Bool
> : (S, S) -> Bool
>= : (S, S) -> Bool