linguist/samples/Type Language/builtin.tl

// built-in types
int#a8509bda ? = Int;
long ? = Long;
double ? = Double;
string ? = String;
null = Null;

vector {t:Type} # [ t ] = Vector t;
coupleInt {alpha:Type} int alpha = CoupleInt<alpha>;
coupleStr {gamma:Type} string gamma = CoupleStr gamma;

/* The name of the type variable is irrelevant: "gamma" could be replaced with "alpha"
  However, the combinator number will depend on the specific choice. */

intHash {alpha:Type} vector<coupleInt<alpha>> = IntHash<alpha>;
strHash {alpha:Type} (vector (coupleStr alpha)) = StrHash alpha;
intSortedHash {alpha:Type} intHash<alpha> = IntSortedHash<alpha>;
strSortedHash {alpha:Type} (strHash alpha) = StrSortedHash alpha;

// custom types
pair x:Object y:Object = Pair;
triple x:Object y:Object z:Object = Triple;

user#d23c81a3 id:int first_name:string last_name:string = User;
no_user#c67599d1 id:int = User;
group id:int title:string last_name:string = Group;
no_group = Group;

---functions---

// Maybe some built-in arithmetic functions; inverse quotes make "identifiers" out of arbitrary non-alphanumeric strings
`+` Int Int = Int;
`-` Int Int = Int;
`+` Double Double = Double;
// ...

// API functions (aka RPC functions)
getUser#b0f732d5 int = User;
getUsers#2d84d5f5 (Vector int) = Vector User;