company-ghci is a company backend that provides completions for the haskell programming language by talking to a ghci process.
company-ghci is available on melpa, so first you will have to configure emacs to use the MELPA repository. Then you can install the package using (package-install).
Add the following code to your init file
(require 'company-ghci) (push 'company-ghci company-backends) (add-hook 'haskell-mode-hook 'company-mode) ;;; To get completions in the REPL (add-hook 'haskell-interactive-mode-hook 'company-mode)
And setup haskell-mode to enable haskell-interactive-mode.
Open a haskell file and load it using haskell-process-load-or-reload (C-c C-l), now when you type something, emacs should offer you some completions.
If you have hoogle installed, you can press
<f1> to open a buffer with the documentation of the highlighted completion candidate.
If you have company-quickhelp, then a popup will appear with the documentation of the highlighted completion candidate.