1 files changed, 26 insertions, 3 deletions
diff --git a/operationscore/Behavior.py b/operationscore/Behavior.py
index 7090a23..507f750 100644
--- a/operationscore/Behavior.py
+++ b/operationscore/Behavior.py
@@ -12,6 +12,7 @@ class Behavior(SmootCoreObject):
     specifically designed to do this (like AddPixelEvent). 
     timeStep is called on every iteration of the LightInstallation
     addInput is called on each individual input received, and the inputs queue"""
+    
     def init(self):
         self.validateArgs('Behavior.params')
         if type(self['Inputs']) != type([]):
@@ -21,34 +22,55 @@ class Behavior(SmootCoreObject):
         self.outGoingQueue = []
         self.lastState = None
         self.behaviorInit()
+    
     def behaviorInit(self):
         pass
+    
     def addMapper(fn):
         def withmap(fn):
             return self.addMapperToResponse(fn())
         return withmap
+    
     def processResponse(self, sensorInputs, recursiveInputs):
         raise Exception('ProcessResponse not defined!')
+    
     def addInput(self, sensorInput):
         self.sensorResponseQueue.append(sensorInput)
+    
     #used for behavior chaining
+    
     def immediateProcessInput(self, sensorInputs, recursiveInputs=[]): 
             (outputs,recursions) = self.processResponse(sensorInputs, \
                     recursiveInputs)
             return self.addMapperToResponse((outputs,recursions))
+
     def addInputs(self, sensorInputs):
         if type(sensorInputs) == type([]):
             [self.addInput(sensorInput) for sensorInput in sensorInputs]
         else:
             self.addInput(sensorInputs)
-    #private
+   
+    @staticmethod 
+    def deepCopyPacket(datapacket):
+        """Returns a deep copy of a behavior data packet (a list of dicts) so that modifying the
+        returned packet will not modify the incoming packet."""
+        ret = []
+        for d in datapacket:
+            d = dict(d)
+            ret.append(d)
+        return ret
+    
     def getLastOutput(self):
         return self.lastState
+    
     def setLastOutput(self, output):
         """Override to modify state.  For example: if you are using a behavior that does uses
         strings for location specification, you will want to override this to point to a single
-        location.  Make sure you keep lastState as a [] of {}.  (List of dicts)"""
-        self.lastState = output
+        location.  Make sure you keep lastState as a [] of {}.  (List of dicts).  Additonally,
+        ensure that you call Behavior.deepCopyPacket on the packet before hand to avoid inadvertent
+        down-stream modifications.  Look at Square.py for an example of this."""
+        self.lastState = Behavior.deepCopyPacket(output)
+    
     def addMapperToResponse(self, responses):
         if self['Mapper'] != None:
             if type(responses) == type(tuple):
@@ -59,6 +81,7 @@ class Behavior(SmootCoreObject):
                         r['Mapper'] = self['Mapper']
                     return responses
         return responses
+    
     def timeStep(self): #TODO: type checking.  clean this up
         (outputs, recursions) = self.processResponse(self.sensorResponseQueue, \
                 self.recursiveResponseQueue)