Autocomplete with a dictionary and hippie-expand

  |   Source

I use company-mode most of the time. Sometimes I use Hippie Expand to autocomplete the English words from a dictionary.

I surely can do this in company-mode too. But I prefer hippie-expand because I choose to make company-mode focus on programming stuff and hippie-expand on writing.

1 Solution

This solution works in any environment.

  • Step1 (OPTIONAL), download english-words.txt and place it under "~/.emacs.d/misc/".
  • Step 2, Copy below setup into ~/.emacs and use key binding "M-/" to complete the word:
(global-set-key (kbd "M-/") 'hippie-expand)

;; The actual expansion function
(defun try-expand-by-dict (old)
  ;; old is true if we have already attempted an expansion
  (unless (bound-and-true-p ispell-minor-mode)
    (ispell-minor-mode 1))

  ;; english-words.txt is the fallback dicitonary
  (if (not ispell-alternate-dictionary)
      (setq ispell-alternate-dictionary (file-truename "~/.emacs.d/misc/english-words.txt")))
  (let ((lookup-func (if (fboundp 'ispell-lookup-words)
                       'ispell-lookup-words
                       'lookup-words)))
    (unless old
      (he-init-string (he-lisp-symbol-beg) (point))
      (if (not (he-string-member he-search-string he-tried-table))
        (setq he-tried-table (cons he-search-string he-tried-table)))
      (setq he-expand-list
            (and (not (equal he-search-string ""))
                 (funcall lookup-func (concat (buffer-substring-no-properties (he-lisp-symbol-beg) (point)) "*")))))
    (if (null he-expand-list)
      (if old (he-reset-string))
      (he-substitute-string (car he-expand-list))
      (setq he-expand-list (cdr he-expand-list))
      t)
    ))

(setq hippie-expand-try-functions-list
      '(;; try-expand-dabbrev
        ;; try-expand-dabbrev-all-buffers
        try-expand-by-dict))

2 Technical details

  • based on ac-ispell
  • lazy load of ispell-mode to speed Emacs startup
  • add a fallback dictionary "english-words.txt" so autocompletion never fails
  • `ispell-lookup-words` or `lookup-words` simply does grep thing, so english-words.txt is just a plain text file.
Comments powered by Disqus