[Haskell-cafe] Should foldl' be added to the post-"Plan FTP" Prelude?

I would love to have foldl' as part of the Prelude. I use it quite frequently and it seems like a beginner trap to have foldl but not foldl' (which is almost always the better choice). I see that foldMap has been added (in addition to all of Monoid and Traversable), why was foldl' left out? It might be good measure to add foldr' as well, although I use that much less frequently. -bob