stupid_simple.py

#!/usr/bin/env python

from tornado import gen
from tornado.ioloop import IOLoop

    
@gen.coroutine
def exception_gets_lost():
    
    print 'got here'
    raise ValueError('swallowed!')
    
    print 'never happens'


if __name__ == '__main__':
    
    import logging
    logging.basicConfig()
    
    exception_gets_lost()
    
    IOLoop.instance().start()