2019-05-20 | Paul Boddie | raw annotate files changeset graph | Experiment with a temporary attribute on objects. This attribute must be cleared when assignments occur, but it should also be cleared when objects escape from functions (which is not yet done). Since the motivation for marking objects as temporary is their re-use in certain operations, the objective is to avoid objects being used in multiple places and still being marked as temporary and potentially undergoing re-use/mutation. Perhaps the only way of guaranteeing exclusive access to an object is if it is provided as a function result and is immediately passed to a function or operation, with this function either mutating the object or ensuring its direct propagation to another such function. | temporary-object-experiment |
1 import operator 2 3 class C: 4 def f(self): pass 5 6 def name(x): 7 print x.__name__ 8 print x.__parent__.__name__ 9 print str(x) 10 11 def attrname(x): 12 print x.f.__name__ 13 print x.f.__parent__.__name__ 14 print str(x.f) 15 16 c = C() 17 print c.__name__ # C 18 print c.__parent__.__name__ # __main__ 19 print str(c) # <__main__.C instance> 20 print C.__name__ # C 21 print C.__parent__.__name__ # __main__ 22 print str(C) # __main__.C 23 print c.f.__name__ # f 24 print c.f.__parent__.__name__ # C 25 print str(c.f) # __main__.C.f 26 print C.f.__name__ # f 27 print C.f.__parent__.__name__ # C 28 print str(C.f) # __main__.C.f 29 30 name(c) # C 31 # __main__ 32 # <__main__.C instance> 33 name(C) # C 34 # __main__ 35 # __main__.C 36 attrname(c) # f 37 # C 38 # __main__.C.f 39 attrname(C) # f 40 # C 41 # __main__.C.f 42 name(c.f) # f 43 # C 44 # __main__.C.f 45 name(C.f) # f 46 # C 47 # __main__.C.f 48 49 # If it were defined, operator.__name__ would be module. 50 51 print operator.__name__ # operator 52 53 # If it were defined, operator.add.__name__ would be function. 54 55 print operator.add.__name__ # add 56 print operator.add.__parent__.__name__ # operator.binary