bytestring VS haskell-mode

The documentation is itself fairly funny, for those who don’t care to click ahead:

> This "function" has a superficial similarity to ‘unsafePerformIO’ but it is in fact a malevolent agent of chaos. It unpicks the seams of reality (and the IO monad) so that the normal rules no longer apply. It lulls you into thinking it is reasonable, but when you are not looking it stabs you in the back and aliases all of your mutable buffers. The carcass of many a seasoned Haskell programmer lie strewn at its feet.

> Witness the trail of destruction:

    https://github.com/haskell/bytestring/commit/71c4b438c675aa360c79d79acc9a491e7bbc26e7

If you bring in efficient strings from bytestring, densely packed arrays from vector, and an in-place sort from vector-algorithms, you can bring it down to 275ms (uses 19MB of mem).

bytestring

Note that this release is broken for Windows.

I've opened https://github.com/haskell/bytestring/issues/455 so the situation can be improved. You're very welcome to chime in on the discussion or to contribute some of the missing documentation yourself! :)

Highlights from the changelog:

Well, ByteString in particular should not have an IsString instance in a new report. That's pretty clear by https://github.com/haskell/bytestring/issues/140 : the concensus is that there is no good solution right now, but it should not have gotten an IsString instance in the first place. If a theoretical new Haskell Report 202x includes OverloadedStrings (as it should) to handle string literals analogously to numeric literals, I'd expect it to not give ByteString (which is really just a collection of octets) an IsString instance, with all it's issues and rattail due to the encoding question being implicitized.

Standard streaming libraries. They are being written by people that make the effort to understand performance and I have a hope that they make sure their streams run in linear space under any optimizations. It is curious and unsettling that we have standard lazy text and byte streams at the same time — and the default lazy lists, of course. I have been doing some work on byte streams and what I found out is that there is no way to check that your folds are actually space constant even if the value in question is a primitive, like say a byte — thunks may explode and then collapse over the run time of a single computation, defying any effort at inspection.

You can use GHCI's debugger through Emacs's haskell-debug-mode (part of the haskell-mode package), and probably through other editor/IDEs as well, a programming editor like Emacs or Vim simply needs to be able to run a GHCI session and send commands to it.

No, I was only using haskell-mode. So I guess this is LSP's fault, then. Not Emacs's fault and not haskell-mode's fault.

If I made it sound like there's something like IntelliSense today, apologies! We've got <https://github.com/haskell/haskell-mode/blob/master/haskell-...>, but it's type-a-command-and-do-a-search: it's not linked in with completion directly in the setups I've seen.

(In practice, I'm usually starting from a slightly different place: I know I want a Frob and I've got a This and a That, so I do :hoogle This -> That -> Frob and get some options. The thought-process is working backwards from the goal more than forwards from one key object in focus. A different way of working, but I'm not convinced it's less effective.)

My point though was that it's an engineering issue, not a fundamental language limitation. ie not a reason all future languages should shun haskell features. The building blocks to do better at completion than haskell curently does are there.

check if you have any similar config to what caused this issue: https://github.com/haskell/haskell-mode/issues/1777 for me

Package-lint has been on my list, but the maintainer, MELPA's Steve Purcell, has been hesitant about NonGNU ELPA in the past (see this discussion), so I have skipped his packages for now, and also because most of the packages he maintains have a "broken" version tag, most of the time -- the reason here is that MELPA adds these manually, and since he understandably is targetting MELPA, there is little interest from his side to fix that.

You can see the expected output in this PR description.

I use haskell-mode. It has a shortcut for loading a module into REPL, and it also runs hasktags for me. That's literally all I use.

Just as a note from my poking around, this is the "official" way to use a nix-shell with haskell-mode: https://github.com/haskell/haskell-mode/blob/3a019e65b504861d7ea23afbfecd14e5ef63e846/haskell-customize.el#L77