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On Tue, Nov 27, 2012 at 9:12 AM, Julien Danjou <julien at danjou.info> wrote:

> On Tue, Nov 27 2012, Eoghan Glynn wrote:
>
> > Yep, transformers should be chainable and capable of discarding
> > (either by explicitly calling down the chain, or by signalling a
> > stopping condition in some other way, e.g. raise an exception
> > or return False or whatever makes sense as a protocol).
>
> Stupid question, but isn't there anything doing that alread in Python?
> That seems so generic. Doug may have an idea?
>

I've seen coroutines based on generator functions used for pipelines like
that, but I'm not sure that's the best solution here. It may be better to
have the logic for passing data between the transformers outside of the
transformers themselves. For example, we expect pollsters to return an
iterable so the manager can interrogate them. Transformers will need to do
that, too, so they can split one event into multiple.

OTOH, I'm still not comfortable with the idea that these things are can be
composed at runtime in such a flexible way. I guess I need to see some more
descriptive use cases to understand why that's an important feature.

Doug


>
> --
> Julien Danjou
> /* Free Software hacker & freelance
>    http://julien.danjou.info */
>
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