On Nov 5, 2012 2:42 PM, "Hiromi ISHII"
Hi, there
On 2012/11/01, at 21:23, Michael Snoyman wrote:
Due to various technical reasons regarding the nature of conduit, you
* Catch exceptions before `lift`ing. * Catch exceptions thrown from the entire Pipe.
Since the exceptions are always originating in the underlying monad,
can't currently catch exceptions within the Pipe monad. You have two options: the first choice is certainly possible in theory, though may require reworking the library you're using a bit.
Thanks. In my case, used library is relatively small so I can rewrite it
But I think it is more convenient doing the same thing without modifying existing code.
The second choice does not match my case because it cannot resume the
One other possibility that I haven't actually tried would be to use
to ignore exception before lifting. process from the place just after an exception occurred. I agree that it would be great if conduit could meet your use case better. I haven't spent enough cycles looking at this yet to determine if the reason we don't have this support is a limitation in the conduit approach itself, or just a limitation in what I was able to implement so far. If you can think of a way to implement more fine-grained exception handling (or anyone else for that matter), I'd love to hear about it. transPipe[1] to catch all of the exceptions, though I'm not sure how well that would work in practice.
The type of the first argument of `transPipe` should be general, so I
think we can't compose it with `catch` function. That makes sense.
-- Hiromi ISHII konn.jinro@gmail.com
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