So here is some minimal working code. It is smart enough to use reason-cli’s Merlin for ReasonML files and opam’s Merlin for OCaml files. I am very interested in any feedback as what other sensible defaults people should have starting out with Emacs for ReasonML/OCaml code. I also included Helm because I love it and want to introduce it to other people. Also, this depends on opam’s library being included before nvm’s. Here is what I mean (from my .zshrc):
# OPAM configuration
. /home/kuwze/.opam/opam-init/init.zsh > /dev/null 2> /dev/null || true
# nvm stuff
export NVM_DIR="$HOME/.nvm"
[ -s "$NVM_DIR/nvm.sh" ] && \. "$NVM_DIR/nvm.sh" # This loads nvm
[ -s "$NVM_DIR/bash_completion" ] && \. "$NVM_DIR/bash_completion" # This loads nvm bash_completion
Anyway, here is the GitHub repository.
And here is the init.el to copy from:
;; note:
;; which ocamlmerlin should spit out:
;; /home/`user_name`/.nvm/versions/node/`some-version`/bin/ocamlmerlin
;; and in `M-x ielm` evaluating the following:
;; (expand-file-name "emacs/site-lisp" (car (process-lines "opam" "config" "var" "share")))
;; should spit out:
;; "/home/`user_name`/.opam/`some-version`/share/emacs/site-lisp"
;; main>------------------------------------------------------------------------
(eval-when-compile
(require 'cl))
(if (fboundp 'paren-set-mode)
(paren-set-mode 'sexp)
(defvar show-paren-style)
(setq show-paren-style 'expression)
(show-paren-mode t))
;; <main------------------------------------------------------------------------
;; packages>--------------------------------------------------------------------
(require 'package)
(setq package-enable-at-startup nil)
(setq package-archives '(("gnu" . "https://elpa.gnu.org/packages/")
("marmalade" . "https://marmalade-repo.org/packages/")
("MELPA" . "https://melpa.org/packages/")
("MELPA Stable" . "http://stable.melpa.org/packages/")))
(package-initialize)
;; Bootstrap `use-package'
(unless (package-installed-p 'use-package)
(package-refresh-contents)
(package-install 'use-package))
(if (require 'quelpa nil t)
(quelpa-self-upgrade)
(with-temp-buffer
(url-insert-file-contents "https://raw.github.com/quelpa/quelpa/master/bootstrap.el")
(eval-buffer)))
;; <packages--------------------------------------------------------------------
;; ;; path>------------------------------------------------------------------------
(if (string-equal system-type "windows-nt")
(progn
(setenv "PATH" (concat
"C:\\Program Files\\Git\\usr\\bin" ";" ;; Unix tools
(getenv "PATH"))))
(progn
(use-package exec-path-from-shell
:ensure t
:config
(when (memq window-system '(mac ns x))
(exec-path-from-shell-initialize)))))
;; ;; <path------------------------------------------------------------------------
;; helm>------------------------------------------------------------------------
(use-package helm
:ensure t
:config
(helm-mode 1)
(helm-popup-tip-mode 1)
(helm-autoresize-mode t)
(setq helm-autoresize-min-height 40)
(setq helm-M-x-fuzzy-match t)
(setq helm-buffers-fuzzy-matching t)
(setq helm-recentf-fuzzy-match t)
(setq helm-lisp-fuzzy-completion t)
(require 'helm-eshell)
(add-hook 'eshell-mode-hook
#'(lambda ()
(define-key eshell-mode-map (kbd "M-l") 'helm-eshell-history)))
;; (global-set-key (kbd "C-s") #'helm-occur) ; using helm-swoop now
(global-set-key (kbd "C-c b") #'helm-filtered-bookmarks)
(global-set-key (kbd "C-c C-b") #'helm-filtered-bookmarks) ; because I am an idiot
(global-set-key (kbd "C-x C-f") #'helm-find-files)
(global-set-key (kbd "C-x b") #'helm-mini)
(global-set-key (kbd "C-x C-b") 'helm-buffers-list)
(global-set-key (kbd "C-h f") 'helm-apropos)
(global-set-key (kbd "C-h r") 'helm-info-emacs)
(global-set-key (kbd "C-h C-l") 'helm-locate-library)
(global-set-key (kbd "C-c f") 'helm-recentf)
(global-set-key (kbd "C-h SPC") 'helm-all-mark-rings)
(global-set-key (kbd "C-c h x") 'helm-register)
(global-set-key (kbd "M-y") 'helm-show-kill-ring)
(global-set-key (kbd "M-x") #'helm-M-x)
(define-key minibuffer-local-map (kbd "C-c C-l") 'helm-minibuffer-history)
(define-key helm-map [backspace] #'backward-kill-word))
(use-package helm-swoop
:ensure t
:config
(global-set-key (kbd "C-s") 'helm-swoop-without-pre-input)
(define-key helm-swoop-map (kbd "C-r") 'helm-previous-line)
(define-key helm-swoop-map (kbd "C-s") 'helm-next-line))
;; <helm------------------------------------------------------------------------
;; ocaml>-----------------------------------------------------------------------
(let ((opam-share (ignore-errors (car (process-lines "opam" "config" "var" "share")))))
(when (and opam-share (file-directory-p opam-share))
(add-to-list 'load-path (expand-file-name "emacs/site-lisp" opam-share))))
(use-package ocp-indent)
(use-package tuareg
:ensure t
:config
(add-hook 'before-save-hook 'ocp-indent-buffer nil t)
(setq auto-mode-alist
(append '(("\\.ml[ily]?$" . tuareg-mode)
("\\.topml$" . tuareg-mode))
auto-mode-alist)))
;; <ocaml-----------------------------------------------------------------------
;; reasonml>--------------------------------------------------------------------
(defun shell-cmd (cmd)
"Returns the stdout output of a shell command or nil if the command returned
an error"
(car (ignore-errors (apply 'process-lines (split-string cmd)))))
(quelpa '(reason-mode :repo "reasonml-editor/reason-mode" :fetcher github :stable t))
(use-package reason-mode
:config
(let* ((refmt-bin (shell-cmd "which refmt")))
(when refmt-bin
(setq refmt-command refmt-bin)))
(add-hook
'reason-mode-hook
(lambda ()
(add-hook 'before-save-hook 'refmt-before-save nil t)
(setq-local merlin-command (shell-cmd "which ocamlmerlin"))
(merlin-mode))))
;; <reasonml--------------------------------------------------------------------
;; merlin>----------------------------------------------------------------------
(use-package merlin
:custom
(merlin-command 'opam)
(merlin-completion-with-doc t)
(company-quickhelp-mode t)
:config
(autoload 'merlin-mode "merlin" nil t nil)
:bind (:map merlin-mode-map
("M-." . merlin-locate)
("M-," . merlin-pop-stack)
("C-c C-o" . merlin-occurrences)
("C-c C-j" . merlin-jump)
("C-c i" . merlin-locate-ident)
("C-c C-e" . merlin-iedit-occurrences))
:hook
;; Start merlin on ml files
(reason-mode . merlin-mode)
(tuareg-mode . merlin-mode)
(caml-mode-hook . merlin-mode))
;; <merlin----------------------------------------------------------------------
;; utop>------------------------------------------------------------------------
(defun reason/rtop-prompt ()
"The rtop prompt function."
(let ((prompt (format "rtop[%d]> " utop-command-number)))
(add-text-properties 0 (length prompt) '(face utop-prompt) prompt)
prompt))
(use-package utop
:config
(defun utop-opam-utop () (progn
(setq-local utop-command "opam config exec -- utop -emacs")
'utop-minor-mode))
(defun utop-reason-cli-rtop () (progn
(setq-local utop-command (concat (shell-cmd "which rtop") " -emacs"))
(setq-local utop-prompt 'reason/rtop-prompt)
'utop-minor-mode))
:hook
(tuareg-mode . utop-opam-utop)
(reason-mode . utop-reason-cli-rtop))
;; <utop------------------------------------------------------------------------
;; company>---------------------------------------------------------------------
(use-package company
:ensure t
:config
(add-hook 'after-init-hook 'global-company-mode)
(setq company-dabbrev-downcase 0)
(setq company-idle-delay 0))
(use-package company-quickhelp
:ensure t
:config
(company-quickhelp-mode 1)
(define-key company-active-map (kbd "C-c h") #'company-quickhelp-manual-begin))
;; <company---------------------------------------------------------------------
;; flycheck>--------------------------------------------------------------------
;; someday these will play nicely with both reasonml and ocaml...
(use-package flycheck
:ensure t
:config
(global-flycheck-mode))
(use-package flycheck-popup-tip
:ensure t
:config
(flycheck-popup-tip-mode))
(use-package flycheck-ocaml
:ensure t
:config
(add-hook 'tuareg-mode-hook
(lambda ()
;; disable Merlin's own error checking
(setq-local merlin-error-after-save nil)
;; enable Flycheck checker
(flycheck-ocaml-setup))))
;; <flycheck--------------------------------------------------------------------
