reload() twice crashes python3

[sam81]

Using python3.2 on Debian Wheezy, if I reload a script using PyCall the first time it works fine, but the second time I get an error. This does not happen with python2.7

 julia> require("ex.jl")

julia> reload("ex.jl")
ERROR: PyError (PyObject_Call) <class 'TypeError'>
TypeError("object of type 'NoneType' has no len()",)
  File "/usr/lib/python3.2/inspect.py", line 266, in getmembers
    for key in dir(object):

 in pyerr_check at /home/sam/.julia/PyCall/src/exception.jl:58
 in pycall at /home/sam/.julia/PyCall/src/PyCall.jl:85
 in pywrap at /home/sam/.julia/PyCall/src/PyCall.jl:518
 in include_from_node1 at loading.jl:91
 in reload_path at loading.jl:114
 in reload at loading.jl:59
at /media/ntfsShared/otherNoSynch/tmp/ex.jl:562

Test case, $ cat ex.jl

using PyCall
pyinitialize("python3")
@pyimport numpy as np
x = np.arange(10)

[stevengj]

That's weird. As far as I can tell, reload doesn't reset the global variables in included modules, so PyCall.initialized will be true on the second load and pyinitialize should (correctly) be a no-op (trying to initialize Python twice would generally crash).

It looks like the problem occurs during @pyimport somehow. Can you just try:

using PyCall
pyinitialize("python3")
@pyimport numpy as np
@pyimport numpy as np

to make sure that it's not simply doing the import twice that is somehow a problem?

[sam81]

I tried your code snippet and no, importing twice doesn't give errors. Also, when reloading twice, errors occur only for some operations, the following for example doesn't cause an error:

using PyCall
pyinitialize("python3")
@pyimport numpy as np
println(np.pi)

If there is np.arange() or the snippet below then reloading twice causes a crash with the same error message:

@pyimport scipy.signal as scisig
f = [0, 0.6, 0.6, 1]; m = [1, 1, 0, 0];
b = scisig.firwin2 (256,f,m)

[stevengj]

Is this fixed now with #49?

[sam81]

Yes, it seems fixed, thanks! Closing.