[Haskell-cafe] Strange error when using Attoparsec and Enumerator

Gregory Collins greg at gregorycollins.net
Sun Dec 5 23:16:23 CET 2010

On Sun, Dec 5, 2010 at 6:14 PM, Crutcher Dunnavant <crutcher at gmail.com> wrote:
> In general, I've observed that debugging broken iterators and
> enumerators is very hard. We probably want some tooling around that;
> I'm looking at an identity enumeratee with debug.trace shoved in, or
> something like that, not sure yet what would help.

Hi Crutcher,

I have some enumerator debug code here:


It's a little bit snap-specific (uses our debug machinery) but helps
me a lot when debugging iteratee stuff. Shouldn't be hard to port.

It contains a debug iteratee (which just prints its input to stdout)
and an iteratee wrapper which logs its input using the Snap debug
mechanism before passing it on to the wrapped iteratee.

Gregory Collins <greg at gregorycollins.net>

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