On Thu, Feb 26, 2004 at 10:48:12AM -0500, David Bolen wrote: [...]
Without addDeferred I need to aggregate the underlying deferreds separately, but more importantly, I need a completely separate loop to install the suppression errbacks, because that has to be done _after_ the Deferreds are stuck into the DeferredList or else that suppression will stop the DeferredList from seeing the error.
Interesting. I think I'd still rather the two loops than the confusing semantics of addDeferred. [...]
Although if DeferredList were to grow a way to specify that it should suppress errors once it has gathered them, I'd probably be just as happy as having addDeferred fixed, since the separate loop for error suppression bugs me more than the need to separately aggregate the Deferreds together before creating the DeferredList. Actually suppressing errors might make me even happier, since needing to suppress the errors separately (noted in the API documentation, but not the HowTo), while making perfect sense to me now, took a while to catch on to initially.
I think adding a 'consumeErrors' or 'suppressErrors' flag might be a good idea... I've put a patch up at http://twistedmatrix.com/bugs/issue528 -- let's continue discussion there. In the meantime, I've checked in the change to deprecate addDeferred, and removed it from the howto. -Andrew.