infrae.comethods

This package provides an helper to write cofunction with the help of Python generators. It provides a decorator that let you write the following paradigm:

from infrae.comethod import cofunction

@cofunction
def processor(**options):
    # Init code
    content = yield
    while content is not None:
         # Work on content, set result in result.
         content = yield result
    # Cleanup code

If you create more of those comethods you can nest them:

import logging

@cofunction
def logger(parent **options):
    logger = logging.getLogger(options.get('name', 'default'))
    logger.info('Start')
    content = yield
    while content is not None:
         result = parent(content)
         logger.info('Processed {0}, got {1}'.format(content, result))
         content = yield result
    # Cleanup code
    logger.info('Done')

And you can use it like this:

with processor() as process:
   with logger(process) as log:
      for item in generator():
          log(item)

Or alternatively:

with processor() as process:
   with logger(process) as log:
      log.map(generator)

Where generator is a generator that yield values to work on. Of course, you can do more interesting things after.

You can find the Mercurial code repository at: https://hg.infrae.com/infrae.comethods/