Emacs 27 Lisp Function Frequency

This page shows a table of emacs lisp functions in order of their usage frequency.

If you are a emacs lisp beginner, you want to master the these functions by order. Go down the list and see which is the first one you don't recognize. A fun way to judge your lisp expertise and challenge friends.

1. setq 55211
2. if 51253
3. defun 40229
4. let 31698
5. and 27604
6. or 21195
7. car 21092
8. when 20185
9. not 18504
10. eq 18458
11. point 16003
12. cdr 15510
13. list 13548
14. nth 13472
15. defvar 12640
16. goto-char 12370
17. while 11145
18. interactive 11034
19. concat 10123
20. define-key 9906
21. cons 9388
22. cond 8918
23. defcustom 7990
24. progn 7987
25. let* 7965
26. unless 7881
27. insert 7683
28. t 7422
29. save-excursion 7302
30. lambda 7279
31. format 7279
32. autoload 6694
33. error 6591
34. point-min 6178
35. const 5667
36. length 5480
37. - 5378
38. = 5344
39. memq 5091
40. message 4964
41. 1+ 4840
42. fn 4833
43. string-match 4821
44. > 4792
45. &optional 4752
46. < 4708
47. looking-at 4594
48. + 4568
49. point-max 4360
50. equal 4282
51. put 4267
52. funcall 4128
53. require 4076
54. push 4072
55. 1- 4025
56. aref 3813
57. fboundp 3710
58. with-current-buffer 3576
59. match-string 3553
60. match-end 3465
61. re-search-forward 3400
62. dolist 3393
63. null 3369
64. match-beginning 3260
65. current-buffer 3010
66. mapcar 2933
67. stringp 2865
68. substring 2816
69. defconst 2747
70. assq 2740
71. forward-line 2665
72. declare-function 2489
73. register-definition-prefixes 2485
74. choice 2422
75. assoc 2324
76. append 2277
77. string= 2246
78. string 2223
79. cadr 2126
80. * 2113
81. apply 2035
82. set 1926
83. make-local-variable 1894
84. forward-char 1861
85. expand-file-name 1853
86. plist-get 1820
87. member 1799
88. >= 1798
89. beginning-of-line 1796
90. car-safe 1778
91. x 1775
92. consp 1769
93. <= 1756
94. file 1629
95. name 1607
96. throw 1600
97. princ 1598
98. nreverse 1587
99. delete-region 1586
100. condition-case 1580
101. defsubst 1527
102. pop 1502
103. zerop 1481
104. repeat 1462
105. arg 1444
106. a 1440
107. provide 1439
108. aset 1421
109. symbol-name 1390
110. org-element-property 1342
111. start 1332
112. add-hook 1325
113. / 1306
114. setf 1294
115. listp 1279
116. buffer-substring 1270
117. defmacro 1247
118. string-to-number 1242
119. intern 1229
120. type 1208
121. function 1206
122. set-buffer 1205
123. get 1193
124. get-text-property 1182
125. class 1178
126. mapconcat 1175
127. file-exists-p 1148
128. skip-chars-forward 1137
129. replace-match 1134
130. setcdr 1119
131. regexp-quote 1103
132. symbolp 1085
133. eobp 1085
134. modify-syntax-entry 1085
135. menu-item 1080
136. char-after 1073
137. max 1064
138. boundp 1061
139. oref 1056
140. defalias 1053
141. delq 1019
142. current-column 1016
143. save-restriction 1015
144. case-fold-search 1014
145. search-forward 992
146. 1 969
147. defgroup 967
148. cl-defmethod 958
149. numberp 953
150. end-of-line 949
151. s 948
152. setcar 931
153. setq-local 923
154. end 916
155. n 915
156. erase-buffer 906
157. default 897
158. beg 890
159. buffer 884
160. catch 881
161. purecopy 875
162. var 867
163. defface 865
164. min 858
165. math-mul 853
166. prog1 851
167. i 850
168. make-sparse-keymap 850
169. &rest 849
170. background 846
171. regexp 842
172. put-text-property 839
173. symbol-value 835
174. pos 831
175. buffer-name 827
176. with-temp-buffer 817
177. mapc 805
178. integerp 804
179. string-equal 802
180. group 789
181. re-search-backward 787
182. skip-chars-backward 785
183. line-beginning-position 776
184. nil 774
185. downcase 772
186. elt 760
187. file-name-directory 759
188. file-name-nondirectory 758
189. map 753
190. nconc 752
191. /= 746
192. symbol 746
193. declare 740
194. narrow-to-region 739
195. make-variable-buffer-local 736
196. eval 735
197. get-buffer-create 727
198. [0-9]+\\ 725
199. bolp 721
200. kill-buffer 712
201. user-error 711
202. run-hooks 704
203. buffer-substring-no-properties 701
204. inhibit-read-only 686
205. unwind-protect 684
206. nthcdr 681
207. pcase 678
208. eval-when-compile 676
209. c-lang-const 671
210. widget-get 664
211. vector 661
212. delete-char 659
213. caar 657
214. \\ 653
215. buf 651
216. widen 651
217. replace-regexp-in-string 644
218. make-string 642
219. save-match-data 639
220. line-end-position 637
221. dir 634
222. math-div 623
223. see 622
224. tag 622
225. overlay-put 619
226. call-interactively 617
227. .*\\ 614
228. set-marker 611
229. ignore-errors 609
230. p 609
231. backward-char 596
232. buffer-file-name 593
233. key 587
234. split-string 586
235. following-char 581
236. signal 576
237. char-before 574
238. filename 572
239. remove-hook 562
240. get-buffer 558
241. select-window 556
242. kbd 555
243. selected-window 554
244. sort 554
245. entry 554
246. file-directory-p 549
247. gethash 545
248. add-to-list 542
249. string-match-p 542
250. value 536
251. str 534
252. define-obsolete-function-alias 532
253. ` 530
254. _ 528
255. prefix-numeric-value 528
256. math-add 526
257. result 525
258. y-or-n-p 523
259. featurep 522
260. point-marker 515
261. bindings--define-key 513
262. mark 512
263. read-string 509
264. , 502
265. read 502
266. 0 497
267. cl-incf 496
268. bobp 488
269. propertize 487
270. functionp 484
271. cddr 483
272. float 478
273. table 478
274. sit-for 474
275. match-string-no-properties 473
276. buffer-string 468
277. dotimes 468
278. copy-sequence 467
279. completing-read 465
280. c 462
281. f 459
282. custom-autoload 459
283. val 456
284. cl-loop 451
285. org-defkey 448
286. get-buffer-window 438
287. switch-to-buffer 438
288. :foreground 434
289. 2 432
290. number-to-string 431
291. b 429
292. math-reject-arg 422
293. from 420
294. forward-sexp 418
295. char-to-string 418
296. form 411
297. item 411
298. reverse 409
299. indent 405
300. [^ 402
301. range 400
302. % 399
303. min-colors 397
304. math-sub 397
305. derived-mode-p 394
306. preceding-char 393
307. widget 393
308. buffer-live-p 389
309. delete-file 388
310. last 388
311. logand 384
312. which 377
313. gnus-message 377
314. debug 376
315. cl-assert 375
316. count 368
317. integer 362
318. insert-file-contents 361
319. event 360
320. alist 358
321. indent-to 355
322. marker-position 353
323. args 353
324. the 352
325. regexp-opt 351
326. [ 349
327. delete 348
328. custom-put-if-not 346
329. window 345
330. eolp 344
331. cdar 343
332. called-interactively-p 341
333. this 341
334. format-message 339
335. files 339
336. set-buffer-modified-p 338
337. file-name-as-directory 337
338. data 334
339. substitute-command-keys 334
340. puthash 334
341. face 334
342. count-lines 332
343. %s 332
344. sym 330
345. save-window-excursion 330
346. prefix 328
347. window-buffer 327
348. find-file-noselect 325
349. marker-buffer 325
350. url 324
351. copy-marker 323
352. make-symbol 322
353. point-at-eol 320
354. add-text-properties 319
355. proc 316
356. buffer-modified-p 314
357. prompt 314
358. math-neg 312
359. define-derived-mode 311
360. file-attributes 311
361. current-indentation 310
362. load 306
363. char 305
364. e 305
365. date 304
366. len 303
367. process 302
368. abs 301
369. expr 300
370. deffoo 299
371. 4 297
372. org-element-type 297
373. upcase 296
374. c-lang-defconst 295
375. res 294
376. insert-buffer-substring 292
377. control 291
378. make-vector 290
379. num 287
380. info 287
381. file-readable-p 286
382. mod 285
383. pop-to-buffer 284
384. article 283
385. body 281
386. l 280
387. obj 280
388. format-time-string 279
389. global-set-key 277
390. selected-frame 275
391. gnus 274
392. vec 271
393. context 270
394. defvar-local 269
395. custom-manual 269
396. defvoo 269
397. doctor-put-meaning 269
398. func 267
399. buffer-size 266
400. point-at-bol 266
401. number 265
402. search-backward 264
403. process-buffer 263
404. line 262
405. move-to-column 261
406. region-beginning 261
407. node 261
408. frame 260
409. define-minor-mode 258
410. semantic-tag-name 258
411. in 257
412. calc-wrapper 256
413. directory-file-name 255
414. limit 255
415. text 253
416. ash 253
417. get-buffer-process 252
418. sexp 252
419. move-marker 251
420. m 250
421. widget-put 249
422. command 247
423. Org 246
424. semantic-lambda 246
425. math-normalize 244
426. dun-mprincl 243
427. pred 242
428. v 240
429. mode 239
430. region-end 239
431. cmd 238
432. make-hash-table 236
433. make-overlay 233
434. write-region 232
435. next-single-property-change 231
436. window-height 231
437. push-mark 231
438. oset 230
439. directory-files 229
440. element 229
441. overlay-get 229
442. int-to-string 229
443. make-marker 226
444. back-to-indentation 226
445. cdr-safe 225
446. read-from-minibuffer 224
447. make-obsolete-variable 224
448. vhdl-insert-keyword 224
449. plist-put 223
450. to 223
451. overlay-start 222
452. process-status 221
453. for 221
454. ding 220
455. getenv 220
456. header 220
457. vectorp 219
458. symbol-function 219
459. obsolete 219
460. org-string-nw-p 219
461. state 218
462. delete-overlay 217
463. e.g. 216
464. prin1-to-string 215
465. msg 214
466. function-item 214
467. define-obsolete-variable-alias 213
468. id 212
469. file-truename 211
470. status 211
471. "" 211
472. buffer-read-only 209
473. buffer-list 209
474. with-output-to-temp-buffer 209
475. default-directory 208
476. executable-find 207
477. register-input-method 207
478. newline 206
479. intern-soft 206
480. recenter 206
481. month 205
482. 3 204
483. save-buffer 203
484. path 202
485. quail-define-package 202
486. read-file-name 200
487. begin 200
488. defclass 200
489. category 200
490. message-fetch-field 199
491. handle 198
492. select 197
493. lookup-key 196
494. ediff-with-current-buffer 196
495. .+\\ 195
496. fset 195
497. host 195
498. event-start 194
499. posn-window 194
500. window-frame 194

Python Script to Count Emacs Lisp Function Frequency

This list is generated by reading all lisp files bundled with GNU Emacs 27.1 of 2020-08-11. Total of 1583 emacs lisp files. Then count the occurrences of the first word after the left parenthesis.

This list is generated by the following Python script.

# -*- coding: utf-8 -*-
# python 3

# purpose: count emacs lisp function frequency list of emacs lisp programs
# see
# http://xahlee.info/emacs/emacs/function-frequency.html
# 2006-10-27, 2020-12-17

# algorithm sketch:
# for each file in a given dir,
# read in the file
# delete comment lines
# break it into a list of temp lines, seperated by (
# for each such line, grab the first word
# put this into a wordlist
# for each in wordlist, add it into a hash key, and if already exist, increase by 1

import os, sys, shutil, re, operator

# /Applications/Emacs27.1.app/Contents/Resources/lisp/
# copy it to a temp directory, ungzip the files
inputDir = "/Users/xah/xx/lisp"

# keys are words, vals are count of occurrences
wordFreq = {}

def countMe(filePath):
    "add words frequency into wordFreq"
    print("reading:", filePath)
    inF = open(filePath, "rb")
    s = str(inF.read(), "iso-8859-1")
    inF.close()

    # ; rid of some comments (on a line by themselves)
    s = s.splitlines()
    s = [x for x in s if not re.search(r"\s*;", x)]
    s = " ".join(s)

    s = s.split("(")

    wordlist = []
    for li in s:
        if li:
            s2 = re.split(r"\s+|\)", li)
            if s2:
                if s2[0]:
                    wordlist.append(s2[0])

    # add to dict
    for wd in wordlist:
        if wd in wordFreq:
            wordFreq[wd] = wordFreq[wd] + 1
        else:
            wordFreq[wd] = 1

for dir_path, subdir_list, file_list in os.walk(inputDir):
    for fname in file_list:
        if re.search(r"\.el$", fname, re.U):
            countMe(os.path.join(dir_path, fname))

print()

# print(wordFreq)

for k, v in sorted(iter(wordFreq.items()), key=operator.itemgetter(1), reverse=True):
    print(k, v)