Emacs/emacs/Spelling

16.4 Checking and Correcting Spelling

This section describes the commands to check the spelling of a single word or of a portion of a buffer. These commands only work if a spelling checker program, one of Hunspell, Aspell, Ispell or Enchant, is installed. These programs are not part of Emacs, but one of them is usually installed on GNU/Linux and other free operating systems. See Aspell in The Aspell Manual.

M-$: Check and correct spelling of the word at point (ispell-word). If the region is active, do it for all words in the region instead.
M-x ispell: Check and correct spelling of all words in the buffer. If the region is active, do it for all words in the region instead.
M-x ispell-buffer: Check and correct spelling in the buffer.
M-x ispell-region: Check and correct spelling in the region.
M-x ispell-message: Check and correct spelling in a draft mail message, excluding cited material.
M-x ispell-change-dictionary RET dict RET: Restart the spell-checker process, using dict as the dictionary.
M-x ispell-kill-ispell: Kill the spell-checker subprocess.
M-TAB

ESC TAB
C-M-i

Complete the word before point based on the spelling dictionary (ispell-complete-word).
M-x flyspell-mode: Enable Flyspell mode, which highlights all misspelled words.
M-x flyspell-prog-mode: Enable Flyspell mode for comments and strings only.

To check the spelling of the word around or before point, and optionally correct it as well, type M-$ (ispell-word). If a region is active, M-$ checks the spelling of all words within the region. See Mark. (When Transient Mark mode is off, M-$ always acts on the word around or before point, ignoring the region; see Disabled Transient Mark.)

Similarly, the command M-x ispell performs spell-checking in the region if one is active, or in the entire buffer otherwise. The commands M-x ispell-buffer and M-x ispell-region explicitly perform spell-checking on the entire buffer or the region respectively. To check spelling in an email message you are writing, use M-x ispell-message; that command checks the whole buffer, except for material that is indented or appears to be cited from other messages. See Sending Mail.

When one of these commands encounters what appears to be an incorrect word, it asks you what to do. It usually displays a list of numbered near-misses—words that are close to the incorrect word. Then you must type a single-character response. Here are the valid responses:

digit: Replace the word, just this time, with one of the displayed near-misses. Each near-miss is listed with a digit; type that digit to select it.
SPC: Skip this word—continue to consider it incorrect, but don’t change it here.
r new RET: Replace the word, just this time, with new. (The replacement string will be rescanned for more spelling errors.)
R new RET: Replace the word with new, and do a query-replace so you can replace it elsewhere in the buffer if you wish. (The replacements will be rescanned for more spelling errors.)
a: Accept the incorrect word—treat it as correct, but only in this editing session.
A: Accept the incorrect word—treat it as correct, but only in this editing session and for this buffer.
i: Insert this word in your private dictionary file so that it will be considered correct from now on, even in future sessions.
m: Like i, but you can also specify dictionary completion information.
u: Insert the lower-case version of this word in your private dictionary file.
l word RET: Look in the dictionary for words that match word. These words become the new list of near-misses; you can select one of them as the replacement by typing a digit. You can use ‘*’ in word as a wildcard.
C-g

X

Quit interactive spell-checking, leaving point at the word that was being checked. You can restart checking again afterward with C-u M-$.
x: Quit interactive spell-checking and move point back to where it was when you started spell-checking.
q: Quit interactive spell-checking and kill the spell-checker subprocess.
?: Show the list of options.

In Text mode and related modes, M-TAB (ispell-complete-word) performs in-buffer completion based on spelling correction. Insert the beginning of a word, and then type M-TAB; this shows a list of completions. (If your window manager intercepts M-TAB, type ESC TAB or C-M-i.) Each completion is listed with a digit or character; type that digit or character to choose it.

Once started, the spell-checker subprocess continues to run, waiting for something to do, so that subsequent spell-checking commands complete more quickly. If you want to get rid of the process, use M-x ispell-kill-ispell. This is not usually necessary, since the process uses no processor time except when you do spelling correction.

Spell-checkers look up spelling in two dictionaries: the standard dictionary and your personal dictionary. The standard dictionary is specified by the variable ispell-local-dictionary or, if that is nil, by the variable ispell-dictionary. If both are nil, the spelling program’s default dictionary is used. The command M-x ispell-change-dictionary sets the standard dictionary for the buffer and then restarts the subprocess, so that it will use a different standard dictionary. Your personal dictionary is specified by the variable ispell-personal-dictionary. If that is nil, the spelling program looks for a personal dictionary in a default location, which is specific to each spell-checker.

A separate dictionary is used for word completion. The variable ispell-complete-word-dict specifies the file name of this dictionary. The completion dictionary must be different because it cannot use the information about roots and affixes of the words, which spell-checking uses to detect variations of words. For some languages, there is a spell-checking dictionary but no word completion dictionary.

Flyspell mode is a minor mode that performs automatic spell-checking of the text you type as you type it. When it finds a word that it does not recognize, it highlights that word. Type M-x flyspell-mode to toggle Flyspell mode in the current buffer. To enable Flyspell mode in all text mode buffers, add flyspell-mode to text-mode-hook. See Hooks. Note that, as Flyspell mode needs to check each word across which you move, it will slow down cursor motion and scrolling commands. It also doesn’t automatically check the text you didn’t type or move across; use flyspell-region or flyspell-buffer for that.

When Flyspell mode highlights a word as misspelled, you can click on it with mouse-2 (flyspell-correct-word) to display a menu of possible corrections and actions. In addition, C-. or ESC-TAB (flyspell-auto-correct-word) will propose various successive corrections for the word at point, and C-c $ (flyspell-correct-word-before-point) will pop up a menu of possible corrections. Of course, you can always correct the misspelled word by editing it manually in any way you like.

Flyspell Prog mode works just like ordinary Flyspell mode, except that it only checks words in comments and string constants. This feature is useful for editing programs. Type M-x flyspell-prog-mode to enable or disable this mode in the current buffer. To enable this mode in all programming mode buffers, add flyspell-prog-mode to prog-mode-hook (see Hooks).