editor_setup.md

title	author
Haskell Editor Setup	Matt Wraith

We're going to do the top 4.

1. Emacs
2. Vim
3. VSCode
4. Atom

Haskell IDE Comparison Chart

Install stack

https://docs.haskellstack.org/en/stable/install_and_upgrade/

$ curl -sSL https://get.haskellstack.org/ | sh

or

$ apt/brew install haskell-stack
$ pacman -S stack

then

$ stack upgrade

You may need to add $HOME/.local/bin to your PATH:

$ export PATH=$HOME/.local/bin:$PATH

ghcid

Everybody can use ghcid. It's a fantastic tool that compiles in the terminal.

$ stack install ghcid

How to use:

$ cd /path/to/your/stack/project
$ ghcid

Emacs

Intero gives you a lot of power. Flychecking code. Querying types of subexpressions:

(package-install 'haskell-mode)
(package-install 'intero)

(require 'haskell)
(require 'haskell-mode)
(require 'intero)

(intero-global-mode 1)

;; If you want to set indentation for spaces
(add-hook 'haskell-mode-hook 'haskell-indentation-mode)
(setq haskell-indentation-layout-offset 4
      haskell-indentation-left-offset 4)

Vim

Ale works well with newest vim:

Plug 'w0rp/ale'
...
let g:ale_set_quickfix = 1
let g:ale_linters = {
\   'haskell': ['stack-ghc'],
\}

If you use neovim, you can also get intero and ghcid plugins:

Plug 'ndmitchell/ghcid', { 'rtp': 'plugins/nvim' }
Plug 'parsonsmatt/intero-neovim'
...
let g:intero_use_neomake = 0 " neomake seems to conflict with ale

For more info on intero-neovim: https://github.com/parsonsmatt/intero-neovim

VSCode

Install https://marketplace.visualstudio.com/items?itemName=Vans.haskero

For all projects that use Haskero, you must:

$ cd /path/to/your/stack/project
$ stack build intero

Atom

$ apm install atom-haskell

https://atom-haskell.github.io/

or for a more minimal install:

apm install language-haskell ide-haskell ide-haskell-cabal ide-haskell-repl

General Advice

• You probably want stack, but it's possible to use cabal or nix or the Haskell Platform.
• Everybody can use ghcid. It's very fast and simple.
• ghc-mod only works well for small projects. It will bog down your editor if you're not careful. This is maybe a problem with the Atom plugin.

Summary

• Emacs -> haskell-mode + intero
• vim -> ale with stack-ghc linter
• neovim -> ghcid + intero
• VSCode -> Haskero (docs)
• Atom -> atom-haskell (simpler subset of atom-haskell: ide-haskell + ide-haskell-cabal)