Maybe include DList

[Anton-Latukha]

DList is still in regular use & considering it is a pretty classical structure - expected to be in use.

Ans since DList actively piggy-backs on GHC abilities of lazy function application - it seems to have strong immunity to regressions, which can happen frequently in other data structures as in Vector.

Therefore it is interesting to see DList results & they are probably much more stable through time & GHC versions & can be a bedrock for comparison.

[Anton-Latukha]

It is very inspiring to find out that that old folk doubtful DList fix for [] recommendation, does not just hold water - but actually was a strong true path to follow all along.

[chrisdone]

Certainly its consing and appending is good and seems to just be a better [] type, you're right.

[Anton-Latukha]

Well, it is logical that if the imperative list is considered a mistake & could not suitable for Haskell laziness - then where is lazy version of a list that is suitable for Haskell. And a Difference List that is.

Also would still note that Haskell strives towards the Philip's Wadler thesis "Listlessness is better than laziness" (1984), so I also have a lot of questions now - which type, [] or DList is simpler to fuse/keep deforestation on & how they comparatively currently optimized by GHC, how far we gone into [] to be able to retroactively adopt the same level of fusion/deforestation for DList - there are only several people that can answer this. & I hope the spread of DList numbers & use would refresh those thoughts to surface in Haskell Committee/GHC & we would at least hear more thoughts on it.