That being said, my experience with Haskell is limited to working on some meta-meta-programming research in college, where every file used at minimum 3 different GHC extensions. So I may be biased.
The number of times I have wished for something like Hoogle when writing Python...
Exception: apl.
are you kidding? most files i see have all of these
I’ve noticed that a _a lot of_ stuff written about FP tries to emulate this fun and easy going style - I wonder why that is. I still refer to clojure’s “re-frame” docs as the epitome of technical literature - a text so good you can read it in its own right just for the fun of it.
I don’t want to diminish other languages’ communities of course, as this is totally anecdotal. I’ve found awesome prose in other places as well (mostly ruby/python) but I just encounter those funny gems more often reading about FP.
Step one, which applies to most functional languages, is knowing how to read a Hindley-Milner type signature [1].
Armed with that you can often gain a surface level understanding of what some function does - and what the program does in aggregate - just by reading type signatures and seeing what calls what.
Hoogle [2] is a good resource for figuring out Haskell syntax, like what's up with all of those $ signs.
Converting OCaml to ReasonML syntax with sketch or reason-tools [3] makes OCaml less foreign.
With basic knowledge of Haskell and ML syntax you'll find many FP languages readable.
[1] https://drboolean.gitbooks.io/mostly-adequate-guide-old/cont...
[2] https://hoogle.haskell.org/
[3] https://reasonml.github.io/docs/en/extra-goodies