made accessing of tail and head from edge more explicit

MaineKuehn · Jul 26, 2018 · 9e133b0 · 9e133b0
1 parent d61c2a2
commit 9e133b0
Showing 1 changed file with 5 additions and 1 deletion.
diff --git a/graphi/edge.py b/graphi/edge.py
@@ -75,7 +75,11 @@ def __class__(self):
         return slice
 
     def __getitem__(self, index):
-        return [self.start, self.stop][index]
+        if index == 0:
+            return self.start
+        elif index == 1:
+            return self.stop
+        raise ValueError
 
     def __iter__(self):
         yield self.start