new type LinkedList, preliminary implementation

kern/compare.go

@@ -20,6 +20,10 @@ func Equal(value1, value2 any) (equal bool) {
 		d1 := value1.(*DictType)
 		d2 := value2.(*DictType)
 		equal = d1.Equals(*d2)
+	} else if IsLinkedList(value1) && IsLinkedList(value2) {
+		ll1 := value1.(*LinkedList)
+		ll2 := value2.(*LinkedList)
+		equal = ll1.Equals(ll2)
 	} else if IsInteger(value1) && IsInteger(value2) {
 		equal = value1.(int64) == value2.(int64)
 	} else if IsString(value1) && IsString(value2) {