Stylish Haskell

Use M-x haskell-mode-stylish-buffer to call stylish-haskell on the current buffer.

On Save

To call it for every save, make sure you have C-x C-s rebound to haskell-mode-save-buffer, and then pop the following somewhere in your Emacs configuration:

(setq haskell-stylish-on-save t)

Or in your custom set variables:

(custom-set-variables '(haskell-stylish-on-save t))

Or you can M-x customize-group haskell and pretend none of this exists!