gistfile1.txt

CONTEXT: start
USER: got resource
ITER: yielding 1
USER: yielding 1
GOT: 1
ITER: yielding 2
USER: yielding 2
GOT: 2
ITER: yielding 3
USER: yielding 3
GOT: 3
ITER: yielding 4
USER: yielding 4
GOT: 4
ITER: yielding 5
USER: yielding 5
GOT: 5
ITER: yielding 6
USER: yielding 6
GOT: 6
ITER: yielding 7
USER: yielding 7
GOT: 7
ITER: yielding 8
USER: yielding 8
GOT: 8
ITER: yielding 9
USER: yielding 9
GOT: 9
ITER: yielding 10
USER: yielding 10
GOT: 10
CONTEXT: done
---------------------------------------------------------------------------
IndexError                                Traceback (most recent call last)
<ipython-input-21-6d377bd1ac3f> in <module>()
     37 
     38 
---> 39 for i in user():
     40     print "GOT: %s" % str(i)

<ipython-input-21-6d377bd1ac3f> in user()
     31     with taker() as resource:
     32         print "USER: got resource"
---> 33         for item in resource:
     34             print "USER: yielding %s" % str(item)
     35             yield item

<ipython-input-21-6d377bd1ac3f> in next(self)
     13 
     14     def next(self):
---> 15         item = self.list[0]
     16         print "ITER: yielding %s" % str(item)
     17         self.list = self.list[1:]

IndexError: list index out of range

test_context.py

# A simple test that demonstrates my problem

from contextlib import contextmanager

class MyIterator(object):
    def __init__(self):
        self.list = [1,2,3,4,5,6,7,8,9,10]

    def __iter__(self):
        return self

    def next(self):
        item = self.list[0]
        print "ITER: yielding %s" % str(item)
        self.list = self.list[1:]
        return item

@contextmanager
def taker():
    print "CONTEXT: start"
    try:
        yield MyIterator()
    finally:
        print "CONTEXT: done"

def user():
    with taker() as resource:
        print "USER: got resource"
        for item in resource:
            print "USER: yielding %s" % str(item)
            yield item


for i in user():
    print "GOT: %s" % str(i)