Add a mechanism for viewing the state and history of a deferred's callbacks as an optional debugging mode

New submission from radix <[email protected]>:

Terry Jones implemented a nice class for tracking deferred history to help debugging strange Deferred problems. It'd be nice to test this code and integrate it into the core of Twisted, with something like defer.setHistoryTracking(True) to turn it on.

The original mailing list post is here:

http://www.twistedmatrix.com/pipermail/twisted-python/2008-October/018535.html

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Type     : enhancement
Component: core
Keywords : 
Priority : normal
Nosy     : 
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http://twistedmatrix.com/trac/ticket/3858