Source Code for Module baxter_dataflow.signals

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27   
28  import inspect 
29  from weakref import WeakKeyDictionary 
30   
31  try: 
32      from weakref import WeakSet 
33  except ImportError: 
34      from weakrefset import WeakSet 
35   
36   
37 -class Signal(object): 
38 -    def __init__(self): 
39          self._functions = WeakSet() 
40          self._methods = WeakKeyDictionary() 
41   
42 -    def __call__(self, *args, **kargs): 
43          for f in self._functions: 
44              f(*args, **kargs) 
45   
46          for obj, functions in self._methods.items(): 
47              for f in functions: 
48                  f(obj, *args, **kargs) 
49   
50 -    def connect(self, slot): 
51          if inspect.ismethod(slot): 
52              if not slot.__self__ in self._methods: 
53                  self._methods[slot.__self__] = set() 
54              self._methods[slot.__self__].add(slot.__func__) 
55          else: 
56              self._functions.add(slot) 
57   
58 -    def disconnect(self, slot): 
59          if inspect.ismethod(slot): 
60              if slot.__self__ in self._methods: 
61                  self._methods[slot.__self__].remove(slot.__func__) 
62          else: 
63              if slot in self._functions: 
64                  self._functions.remove(slot) 
65