Private spacemacs layer to try out Chris Done's Intero mode for haskell

packages.el

;; 1. place this in ~/.emacs.d/private/intero/packages.el

;; 2. add intero, syntax-checking and auto-completion to your
;; ~/.spacemacs layer configuration & remove the haskell layer
;; if you were using that before

;; 3. make sure you have stack installed http://haskellstack.org

;; 4. fire up emacs & open up a stack project's source files

(defconst intero-packages
  '(company
    flycheck
    haskell-mode
    hindent
    (intero :location (recipe
                       :repo "chrisdone/intero"
                       :fetcher github
                       :files ("elisp/intero.el")))))

(defun intero/init-company-mode ()
  (use-package company-mode))

(defun intero/init-hindent ()
  (use-package hindent))

(defun intero/init-haskell-mode ()
  (use-package haskell-mode))
(defun intero/post-init-haskell-mode ()
  (add-hook 'haskell-mode-hook 'hindent-mode)
  (add-hook 'haskell-mode-hook 'intero-mode))

(defun intero/init-intero ()
  (use-package intero))
(defun intero/post-init-intero ()
  (flycheck-add-next-checker 'intero '(warning . haskell-hlint)))

When you issue the command C-c C-t to get the type under point, is the type message in the echo area quickly shadowed by a Wrote /path/to/file message?

EDIT: See below for (partial) solution.

The problem I mentioned above is created when the layer syntax-checking is enabled along with the intero layer, probably because intero ships it's own version of flycheck.

For a quick patch, one could remove the syntax-checking layer from .spacemacs, or disabling it locally via SPC t s. This last option has the unwanted consequence of disabling the features of flycheck that are shipped with intero.

I put this file in my .emacs.d/private/intero folder, added the new layers and removed haskell, and removed a hook to haskell-mode. When I try opening a stack source file, intero is built and then a buffer containing the following pops up:

**Usage: stack ghci [TARGET] [--ghc-options OPTION] [--with-ghc GHC] [--no-load]
[--package ARG] [--main-is TARGET]
Run ghci in the context of project(s) (experimental)

---

This is the buffer where Emacs talks to intero. It's normally hidden,
but a problem occcured.

It may be obvious if there is some text above this message
indicating a problem.

The process ended. Here is the reason that Emacs gives us:

exited abnormally with code 1

For troubleshooting purposes, here are the arguments used to launch intero:

stack ghci --with-ghc intero --docker-run-args=--interactive=true --tty=false --no-load --no-build --ghci-options "-odir=/tmp/intero368i4W" --ghci-options "-hidir=/tmp/intero368i4W" curses-irc-reader

After fixing this problem, you could switch back to your code and
run M-x intero-restart to try again.

You can kill this buffer when you're done reading it.**

I tried running the given stack command from the shell, and got the same "Usage" error. It looks like the stack command arguments are somehow incorrect.

Am I doing something wrong?

@rybern are you running the latest version of stack?

@meditans I am running into the same problem. I certainly don't want to disable the amazing fly checking as I type feature. Let me know if you come up with any work-arounds

@gregwebs if you remove it from the layers in your .spacemacs it doesn't seem to disable it (and I suppose that's because intero ships with its own flycheckin or something like that). But it will disable flycheck for other languages.

Worked well for me, but the intero repl behaved like a pure text buffer instead of a command-line - maybe the shell-mode was not enabled?

@gregwebs @meditans I merged in a patch which gets rid of the "Wrote buffer .." message: chrisdone-archive/intero#54

I'm guessing this on first start after activating this:

Compiling file /home/magnus/.emacs.d/elpa/intero-20160606.926/intero.el at Mon Jun  6 09:56:19 2016
intero.el:50:1:Error: Cannot open load file: no such file or directory, flycheck

Emacs 24.5 on Arch Linux, and the syntax-checking layer is activated.

@magthe yeah, I got the same error

@chrisdone thanks, that patch works! I just had to go into the elpa package list and update intero.

Any thoughts on what keybindings this could run under? Perhaps SPC m .. like the current haskell layer uses, since it's not meant to be mixed?

I am trying to expand on this layer to add keybindings that are consistent with other spacemacs layers, e.g. using SPC m as leader key and mapping other commands with mnemonic but I cannot it work even with the simplest example:

(defun intero/init-intero ()
  (use-package intero
    :config
    (progn
      (spacemacs/set-leader-keys-for-major-mode 'intero-mode "ml" 'intero-repl-load))
    ))

I am a total noob with spacemacs... Any idea?