Perplexing assignment behavior with h5py object as instance variable

Question

I\'m using h5py to access HDF5 files and store the h5py File objects in a class. But I\'m experiencing some strange behavior in attempting to reassign a closed h5py file ins

Answer 1

Not sure if this will help, but searching through the source code I found this (abbreviated):

class HLObject(object):
    def __nonzero__(self):
        register_thread()
        return self.id.__nonzero__()

class Group(HLObject, _DictCompat):
    ...

class File(Group):
    def __repr__(self):
        register_thread()
        if not self:
            return ""
        return '' % \
            (os.path.basename(self.filename), self.mode,
             _extras.sizestring(self.fid.get_filesize()))

Because there is no __str__ method, __repr__ is called to produce the output, and __repr__ first calls register_thread(), then checks to see if self is alive (better known as evaluating to True or False).

Python then searches the classes until it finds __nonzero__ (which again calls register_thread()), then returns self.id.__nonzero__(), which is apparently returning False.

So, you are correct in that the issue is not with the name binding (assignment), but why register_thread and/or self.id is bombing out on you, I do not know.