Hi, I've got a conduit thing that yields infinitely many values and never exits, which I've given the type ConduitM https://hackage.haskell.org/package/conduit-1.2.6/docs/Data-Conduit.html#t:C... () o m Void - a bit like Source m o = ConduitM https://hackage.haskell.org/package/conduit-1.2.6/docs/Data-Conduit.html#t:C... () o m () except that it can't exit due to the Void. (One side-question: why is Source m o not ConduitM https://hackage.haskell.org/package/conduit-1.2.6/docs/Data-Conduit.html#t:C... Void o m ()?) I would now like to get the first item it yields; I'm currently using Data.Conduit.List.head but of course this returns a Maybe o in case the upstream thing exits. Is there a way to do this without that Maybe? I can't see anything obvious, but nor can I think of a terribly good reason why not. One thing that I was pondering was a kind of fuse operator with a type like ... ConduitM https://hackage.haskell.org/package/conduit-1.2.6/docs/Data-Conduit.html#t:C... a b m r1 -> ConduitM https://hackage.haskell.org/package/conduit-1.2.6/docs/Data-Conduit.html#t:C... b c m r2 -> ConduitM https://hackage.haskell.org/package/conduit-1.2.6/docs/Data-Conduit.html#t:C... a c m (Either r1 r2) ... which returns the result of whichever thing exits first. Does such a thing exist? Does it even make sense? If it existed, I think I could use it here as it'd specialise to ConduitM https://hackage.haskell.org/package/conduit-1.2.6/docs/Data-Conduit.html#t:C... () o m Void -> ConduitM https://hackage.haskell.org/package/conduit-1.2.6/docs/Data-Conduit.html#t:C... o Void m o -> ConduitM https://hackage.haskell.org/package/conduit-1.2.6/docs/Data-Conduit.html#t:C... () Void m (Either Void o) and of course (Either Void o) is isomorphic to o so I'd be home and dry. Having written this, I'm now also struggling to work out what the thing of type ConduitM https://hackage.haskell.org/package/conduit-1.2.6/docs/Data-Conduit.html#t:C... o Void m o would be. Maybe I'm going about this all the wrong way, or maybe I'm just confused? Any help greatly appreciated! Cheers, David