※ 引述《xinu (xinu)》之铭言： : 请问一下在python里 : 有办法藉由class里的某个member(attribute) : 就找到该Class吗? : 假设c里面是这样写的话 : struct A { : .... : .... : int a; //certain member : }; : struct A a; : void *ptr = &a.a; : ptr= ptr - ((struct A *)0)->a; : ptr这时候会等於 &a; : 这样子的暴力手段python有办法实作出来吗? : 或是有什麽其他替代方案? 我看introspection里好像没提到这段... python object 里的 attr 都是 reference , 所以有可能多个 object 的某 attr 都指向同一个 reference . 这一点与 C 有很大的不同. 硬要做到这种功能不是不行，底下是用间接的方法列举 object 来找. 因为我找不到 python 有类似 ruby 的 ObjectSpace 功能，所以自己做一个. import weakref ObjectSpace = {} class OSObject: @classmethod def contain_of(cls, target, attr): os_cls = ObjectSpace.setdefault(cls, []) # # clean up invalid objects # os_cls[:] = [ obj for obj in os_cls if obj() ] objs = [obj() for obj in os_cls if obj() and target is getattr(obj(), attr) ] return objs def os_store(self): cls = self.__class__ os_cls = ObjectSpace.setdefault(cls, []) os_cls.append(weakref.ref(self)) def __init__(self, array): self.os_store() self.array = array if __name__ == '__main__': target1 = [1, 2, 3] target2 = [4, 5, 6] target3 = [7, 8, 9] a = OSObject(target1) b = OSObject(target2) c = OSObject(target1) print "object a: ", a print "object b: ", b print "object c: ", c print "find objects which contain target1 as attribute 'array'" print OSObject.contain_of(target1, "array") print "find objects which contain target2 as attribute 'array'" print OSObject.contain_of(target2, "array") print "find objects which contain target3 as attribute 'array'" print OSObject.contain_of(target3, "array") result: object a: <__main__.OSObject instance at 0x81b1d4c> object b: <__main__.OSObject instance at 0x81bcd8c> object c: <__main__.OSObject instance at 0x81bcdac> find objects which contain target1 as attribute 'array' [<__main__.OSObject instance at 0x81b1d4c>, # a <__main__.OSObject instance at 0x81bcdac>] # c find objects which contain target2 as attribute 'array' [<__main__.OSObject instance at 0x81bcd8c>] # b find objects which contain target3 as attribute 'array' [] # None --

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