README.md

test pickle for instance method

pickling instance method failed for python2

py2.7.out

------
cmath
sin
p0
.
------
(i__main__
C
p0
(dp1
b.
------
Traceback (most recent call last):
  File "test.py", line 17, in <module>
    test()
  File "test.py", line 14, in test
    print(pickle.dumps(c.f))
  File "/usr/lib/python2.7/pickle.py", line 1380, in dumps
    Pickler(file, protocol).dump(obj)
  File "/usr/lib/python2.7/pickle.py", line 224, in dump
    self.save(obj)
  File "/usr/lib/python2.7/pickle.py", line 306, in save
    rv = reduce(self.proto)
  File "/usr/lib/python2.7/copy_reg.py", line 70, in _reduce_ex
    raise TypeError, "can't pickle %s objects" % base.__name__
TypeError: can't pickle instancemethod objects

py3.6.out

------
b'\x80\x03cmath\nsin\nq\x00.'
------
b'\x80\x03c__main__\nC\nq\x00)\x81q\x01.'
------
b'\x80\x03cbuiltins\ngetattr\nq\x00c__main__\nC\nq\x01)\x81q\x02X\x01\x00\x00\x00fq\x03\x86q\x04Rq\x05.'

test_method_pickle.py

class C:
  def f(x):
    return x+1

def test():
  import pickle
  import math
  print('------')
  print(pickle.dumps(math.sin))
  c = C()
  print('------')
  print(pickle.dumps(c))
  print('------')
  print(pickle.dumps(c.f))

if __name__ == '__main__':
  test()