(disclaimer: I talked about this in private with Ben but it deemed necessary to post that publicly)
(TL;DR: We need to avoid pleasing every possible group of users at once, and as such the better we can figure out our target group, the better the end result will be, that is why we need to split some of the changes we would all like to see between base and a new prelude)
At the moment, what the Prelude is trying to achieve is unclear beyond the simple “default exports”. It does not particularly help neither library writers, beginners, compiler engineers, nor application developers.
As a consequence, we have seen many alternative preludes trying to address the concerns of those categories. We have the preludes that pride themselves as being an application development framework, with effect tracking, logging, database, etc), those who provide better data-structures and re-exports other packages, and so on.
As such, I think it is important to have this discussion about a prevalent alternative prelude under the prism of “Which category do we aim to serve?”. The library writers certainly may not want to have mtl and transformers re-exported! But they want head :: NonEmpty a, which is also something that would benefit the beginners! The application developers may, on the other hand, need to have a more off-the-shelf access to ReaderT and Text-first environments, as well as having Vector and HashMap coming in handy.
Now, the reader may think “Well, isn’t that what the Haskell Platform was about?”, to which I will reply that whilst the Haskell Platform did in fact provide a set of blessed libraries, they were also pre-compiled and efforts were invested to ease the burden of development on the tooling/package handling side of things.
To directly reply to some of Ben’s points:
[…] away with partial functions and known laziness foot-guns (e.g. foldl)
I think we can have this problem solved in base
re-exports the libraries that nearly every Haskell program uses (e.g. containers, text, bytestring, deepseq, etc.)
I think we should solve this problem outside of base.
Now, to answer the question Ben asked:
Have you considered using an alternative prelude in the past? Did you end up doing so? If not, why?
I do at the moment use relude by Kowainik for application development and the occasional library that is so tightly coupled to me that I include it anyway (but would rather not, because of the deps footprint).
I initially did not use one because the ones that existed before were either abandonned or did not resonate with me, or wanted to much to tell me how to do things.
So, relude did check some of the boxes that had repelled me from alternative preludes at first, and that is why I am using it this day.