Handle 'None' in YAML Directions.

diff --git a/cookbook/cookbook.py b/cookbook/cookbook.py
index fdfae2c5053cf216e000e3de9d7b8bbd564e3c52..24a70feeda9eb34ac151543eadadbf4810267534 100644 (file)
--- a/cookbook/cookbook.py
+++ b/cookbook/cookbook.py
@@ -353,6 +353,8 @@ class Directions (list):
                                             for paragraph in self]))
 
     def from_yaml(self, string):
+        if string == None:
+            return
         while len(self) > 0:
             self.pop()
         for paragraph in string.split('\n\n'):