Implements has_next() method in list item

04_linkedList/ll.py

@@ -5,13 +5,30 @@ Implementation of Linked Lists
 2013/12
 """
 
-
 class SingleListItem():
     """
     Item from a Single Linked List.
     Contains only a previous next element, and a value
-    """
+    """		
-    def __init__(self, value, next):
+    def __init__(self, value, nexti=None):
         self.value = value
-        self.next = next
+        self.nexti = nexti
 
+    def has_next(self):
+		"""
+		Returns True if the item has a next value
+		"""
+		return not (self.nexti is None)
+		
+class SingleLinkedList():
+	"""
+	Linked list with only one link between items.
+	The list can only be traversed one way"""
+	
+	def __init__():
+		self.root= SinglelistItem(None, None) # The head
+
+if __name__ == "__main__":
+	a = 12
+	t = SingleListItem(12)
+	print t.has_next()

04_linkedList/ll_test.py

@@ -13,9 +13,18 @@ class test_single_linked_list_item(unittest.TestCase):
     def test_item(self):
 
         a = 12
-        t = SingleListItem(12, None)
+        t = SingleListItem(12)
 
         self.assertEqual(a, t.value)
 
+	def test_has_next(self):
+		a = 12
+        t = SingleListItem(12)
+
+        self.assertEqual(False, t.has_next())
+        
+        b = SingleListItem(13, t)
+        self.assertEqual(True, b.has_next())
+
 if __name__ == "__main__":
-    unittest.main()
+    unittest.main()