├── .gitignore
├── .travis.yml
├── Makefile
├── README.md
├── key-quiz.el
└── LICENSE


/.gitignore:
--------------------------------------------------------------------------------
 1 | # Compiled
 2 | *.elc
 3 | 
 4 | # Packaging
 5 | .cask
 6 | 
 7 | # Backup files
 8 | *~
 9 | 
10 | # Undo-tree save-files
11 | *.~undo-tree
12 | 


--------------------------------------------------------------------------------
/.travis.yml:
--------------------------------------------------------------------------------
 1 | # From: https://github.com/npostavs/emacs-travis
 2 | 
 3 | language: generic
 4 | sudo: false
 5 | dist: xenial
 6 | 
 7 | env:
 8 |   matrix:
 9 |     - EMACS_VERSION=26.2
10 |     - EMACS_VERSION=26.3
11 |     - EMACS_VERSION=master
12 |   allow_failures:
13 |     - env: EMACS_VERSION=master
14 | 
15 | install:
16 |   - curl -LO https://github.com/npostavs/emacs-travis/releases/download/bins/emacs-bin-${EMACS_VERSION}.tar.gz
17 |   - tar -xaf emacs-bin-${EMACS_VERSION}.tar.gz -C /
18 |   # Configure $PATH: Emacs installed to /tmp/emacs
19 |   - export PATH=/tmp/emacs/bin:${PATH}
20 |   - emacs --version
21 | 
22 | script:
23 |   - make check
24 | 


--------------------------------------------------------------------------------
/Makefile:
--------------------------------------------------------------------------------
 1 | NOOUTPUT = { ! grep '^'; }
 2 | 
 3 | define CUSTOM_GAME
 4 | (key-quiz nil (quote (("C-f o o" . "foo-cmd")
 5 |                       ("C-b a r" . "bar-cmd")
 6 |                       ("C-M-t e s t" . "test-cmd")
 7 | 	              ("M-m e t a" . "meta-cmd"))))
 8 | endef
 9 | export CUSTOM_GAME
10 | 
11 | check:
12 | 	emacs --batch --eval '(byte-compile-file "key-quiz.el")' 2>&1 | $(NOOUTPUT)
13 | 	emacs --batch --eval '(find-file "key-quiz.el")' \
14 | 		      --eval '(checkdoc-current-buffer)' 2>&1 | $(NOOUTPUT)
15 | 
16 | run:
17 | 	emacs -q -l key-quiz.el --eval '(key-quiz)'
18 | 
19 | run-reverse:
20 | 	emacs -q -l key-quiz.el --eval '(key-quiz t)'
21 | 
22 | run-custom:
23 | 	emacs -q -l key-quiz.el --eval "$$CUSTOM_GAME"
24 | 


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/README.md:
--------------------------------------------------------------------------------
 1 | # key-quiz
 2 | [![MELPA](https://melpa.org/packages/key-quiz-badge.svg)](https://melpa.org/#/key-quiz)
 3 | [![Build Status](https://travis-ci.org/federicotdn/key-quiz.svg?branch=master)](https://travis-ci.org/federicotdn/key-quiz)
 4 | ![License](https://img.shields.io/github/license/federicotdn/key-quiz.svg)
 5 | 
 6 | Key Quiz is a game for GNU Emacs (26+) where the player must type in key sequences corresponding to different Emacs commands, chosen at random.
 7 | 
 8 | The game includes a variant, called "reverse mode", where the player is given a key sequence and then must answer with the corresponding command.
 9 | 
10 | ## Installation
11 | You can install Key Quiz by using the `package-install` command (make sure [MELPA](https://melpa.org/) is included in your package sources):
12 | 
13 | <kbd>M-x</kbd> `package-install` <kbd>[RET]</kbd> `key-quiz` <kbd>[RET]</kbd>
14 | 
15 | Alternatively, you can just add `key-quiz.el` to your `load-path`.
16 | 
17 | ## Playing
18 | To play Key Quiz, use <kbd>M-x</kbd> `key-quiz` <kbd>[RET]</kbd>.
19 | 
20 | By default, Key Quiz will quiz the player on keys set in Fundamental mode. This can be changed by setting the variable `key-quiz-use-mode` to another major mode command, such as `'org-mode`. Other aspects of the game can also be customized by configuring variables; see <kbd>M-x</kbd> `customize-group` <kbd>[RET]</kbd> `key-quiz` <kbd>[RET]</kbd>.
21 | 
22 | You can also play Key Quiz by calling the `key-quiz` function directly. By doing this, it is possible to pass a custom list of key-command pairs from which the player will be quizzed with. For example:
23 | ```elisp
24 | (key-quiz nil '(("C-x f b"   . "foo-bar")
25 |                 ("C-c b f f" . "bar-foo-foo")
26 |                 ("C-c q b"   . "quux-baz")
27 |                 ("C-x C-f"   . "find-file")
28 |                 ("C-c q f"   . "quuz-foo")
29 |                 ("C-c b q"   . "bar-quuz")))
30 | ```
31 | 
32 | More detailed instructions can be found at <kbd>C-h f</kbd> `key-quiz` <kbd>[RET]</kbd>.
33 | 
34 | ## Screenshots
35 | <p align="center">
36 |   <img src="https://user-images.githubusercontent.com/6868935/59036677-1f8e0480-8846-11e9-9087-93058a35ce71.png" alt="Key Quiz" title="" />
37 | </p>
38 | 
39 | <p align="center">
40 |   <img src="https://user-images.githubusercontent.com/6868935/59046014-89fb7080-8857-11e9-9d19-eed1465c2bac.png" alt="Key Quiz" title="" />
41 | </p>
42 | 
43 | ## Alternatives
44 | - [keywiz.el](https://github.com/deestan/emacs/blob/master/emacs-goodies-el/keywiz.el) - Emacs key sequence quiz by Jesper Harder.
45 | - [shortcutFoo](https://www.shortcutfoo.com/) - Learn shortcuts and commands.
46 | 
47 | ## License
48 | Distributed under the GNU General Public License, version 3.
49 | 


--------------------------------------------------------------------------------
/key-quiz.el:
--------------------------------------------------------------------------------
  1 | ;;; key-quiz.el --- Emacs Keys Quiz  -*- lexical-binding: t -*-
  2 | 
  3 | ;; Copyright (c) 2020 Federico Tedin
  4 | 
  5 | ;; Author: Federico Tedin <federicotedin@gmail.com>
  6 | ;; Homepage: https://github.com/federicotdn/key-quiz
  7 | ;; Keywords: games
  8 | ;; Package-Version: 0.1
  9 | ;; Package-Requires: ((emacs "26"))
 10 | 
 11 | ;; This program is free software; you can redistribute it and/or modify
 12 | ;; it under the terms of the GNU General Public License as published by
 13 | ;; the Free Software Foundation, either version 3 of the License, or
 14 | ;; (at your option) any later version.
 15 | 
 16 | ;; This program is distributed in the hope that it will be useful,
 17 | ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
 18 | ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 19 | ;; GNU General Public License for more details.
 20 | 
 21 | ;; You should have received a copy of the GNU General Public License
 22 | ;; along with this program.  If not, see <http://www.gnu.org/licenses/>.
 23 | 
 24 | ;;; Commentary:
 25 | 
 26 | ;; Key Quiz is a game where the player must type in key sequences
 27 | ;; corresponding to different Emacs commands, chosen at random.
 28 | 
 29 | ;; The game includes a variant, called "reverse mode", where the
 30 | ;; player is given a key sequence and then must answer with the
 31 | ;; corresponding command.
 32 | 
 33 | ;;; Code:
 34 | 
 35 | (require 'subr-x)
 36 | (require 'seq)
 37 | (require 'cl-lib)
 38 | (require 'gamegrid)
 39 | 
 40 | (defgroup key-quiz nil
 41 |   "Play an Emacs Key Quiz."
 42 |   :prefix "key-quiz-"
 43 |   :group 'games)
 44 | 
 45 | (defcustom key-quiz-reverse-hints-count 6
 46 |   "Number of hints to show when playing in 'reverse mode'."
 47 |   :type 'integer)
 48 | 
 49 | (defcustom key-quiz-partial-answer-score 5
 50 |   "Number of points awarded for each correct part of a key answered."
 51 |   :type 'integer)
 52 | 
 53 | (defcustom key-quiz-wrong-answer-score -10
 54 |   "Penalty for answering a question incorrectly."
 55 |   :type 'integer)
 56 | 
 57 | (defcustom key-quiz-game-length 20
 58 |   "Number of questions per game."
 59 |   :type 'integer)
 60 | 
 61 | (defcustom key-quiz-matching-regexp "^<?[MC]"
 62 |   "Regexp used to match valid mappings in the quiz.
 63 | The regexp should start with ^ and be valid for
 64 | `delete-non-matching-lines'.  The regexp is not used when playing a
 65 | custom game."
 66 |   :type 'string)
 67 | 
 68 | (defcustom key-quiz-use-mode 'fundamental-mode
 69 |   "Mode to use when fetching key-command list.
 70 | This variable is ignored when playing a custom game."
 71 |   :type 'function)
 72 | 
 73 | (defvar-local key-quiz--keys nil
 74 |   "Currently loaded keys and commands.")
 75 | 
 76 | (defvar-local key-quiz--score 0
 77 |   "Current score.")
 78 | 
 79 | (defvar-local key-quiz--game-reverse nil
 80 |   "Non-nil if currently playing in 'reverse mode'.")
 81 | 
 82 | (defvar-local key-quiz--custom-keys nil
 83 |   "Custom key-command alist specified by the player.")
 84 | 
 85 | (defvar-local key-quiz--round 0
 86 |   "Current round number.")
 87 | 
 88 | (defvar-local key-quiz--last-state nil
 89 |   "Last game state. Used for resuming.")
 90 | 
 91 | (defvar-local key-quiz--prompt-pos nil
 92 |   "Buffer position of last prompt. Used when deleting Pause text.")
 93 | 
 94 | (defvar-local key-quiz--score-file "key-quiz-scores"
 95 |   "File for holding Key Quiz high scores.")
 96 | 
 97 | (defface key-quiz-question '((t :inherit bold))
 98 |   "Face for Key Quiz questions.")
 99 | 
100 | (defface key-quiz-correct '((t :inherit success
101 | 			       :weight bold))
102 |   "Face for Key Quiz correct answers.")
103 | 
104 | (defface key-quiz-partial '((t :inherit warning
105 | 			       :weight bold))
106 |   "Face for Key Quiz partially correct answers.")
107 | 
108 | (defface key-quiz-wrong '((t :inherit error
109 | 			     :weight normal))
110 |   "Face for Key Quiz wrong answers.")
111 | 
112 | (defface key-quiz-answer '((t :inherit minibuffer-prompt
113 | 			      :weight bold))
114 |   "Face for Key Quiz provided answers.")
115 | 
116 | (defvar key-quiz-mode-map
117 |   (let ((map (make-sparse-keymap)))
118 |     (define-key map (kbd "r") 'key-quiz--restart)
119 |     (define-key map (kbd "c") 'key-quiz--resume)
120 |     (define-key map (kbd "q") 'key-quiz--quit)
121 |     (define-key map (kbd "RET") 'ignore)
122 |     map))
123 | 
124 | (define-derived-mode key-quiz-mode special-mode "Key Quiz"
125 |   "Key Quiz mode.
126 | Shows current score and more information on the header line."
127 |   (setq header-line-format
128 | 	'((:eval (propertize (format "Score: %s"
129 | 				     (int-to-string key-quiz--score))
130 | 			     'font-lock-face 'bold))
131 | 	  " - Use 'C-g r' to restart the game, 'p RET' to pause")))
132 | 
133 | (defun key-quiz--get-keys ()
134 |   "Return an alist of (KEY . COMMAND), representing active keybindings.
135 | Many keys and commands are filtered out to only include those which
136 | the player is likely to remember or guess correctly.  The initial key
137 | list is generated using `describe-buffer-bindings' on
138 | `key-quiz-use-mode'."
139 |   (let (keys)
140 |     (with-temp-buffer
141 |       (funcall key-quiz-use-mode)
142 |       (describe-buffer-bindings (current-buffer))
143 |       (goto-char (point-min))
144 |       (delete-non-matching-lines key-quiz-matching-regexp)
145 |       (delete-matching-lines
146 |        "Prefix Command\\|Keyboard Macro\\|mouse\\|C-g\\|\\.\\.")
147 |       (while (not (eobp))
148 | 	(let ((line (buffer-substring (line-beginning-position)
149 | 				      (line-end-position))))
150 | 	  (string-match "\\(.+\\)[[:blank:]]+\\([^[:blank:]]+\\)" line)
151 | 	  (let ((key (match-string 1 line))
152 | 		(command (match-string 2 line)))
153 | 	    ;; Do not include C-g in keys list
154 | 	    (when (and (not (string= command "keyboard-quit"))
155 | 		       (commandp (intern-soft command)))
156 | 	      (push (cons (string-trim key) command) keys))))
157 | 	(forward-line 1)))
158 |     keys))
159 | 
160 | (defun key-quiz--shuffle-list (list)
161 |   "Shuffles LIST randomly, modifying it in-place.
162 | Returns LIST."
163 |   (dolist (i (reverse (number-sequence 1 (1- (length list)))))
164 |     (let ((j (random (1+ i)))
165 | 	  (tmp (elt list i)))
166 |       (setf (elt list i) (elt list j))
167 |       (setf (elt list j) tmp)))
168 |   list)
169 | 
170 | (defun key-quiz--insert-separator ()
171 |   "Insert a horizontal separator in the current buffer."
172 |   (newline)
173 |   (insert (propertize (make-string (window-width) ? )
174 | 		      'font-lock-face 'underline
175 | 		      'rear-nonsticky t))
176 |   (newline))
177 | 
178 | (defun key-quiz--keys-distance (k1 k2)
179 |   "Return (NUMBER . EQUALS).
180 | NUMBER is the amount of inputs K1 and K2
181 | share, and EQUALS is (string= K1 K2)."
182 |   (if (not (string= k1 k2))
183 |       (let ((l1 (split-string k1))
184 | 	    (l2 (split-string k2))
185 | 	    (matches 0))
186 | 	(dotimes (i (length l1))
187 | 	  (when (and (< i (length k2))
188 | 		     (string= (nth i l1)
189 | 			      (nth i l2)))
190 | 	    (setq matches (1+ matches))))
191 | 	(cons matches nil))
192 |     (cons (length (split-string k1)) t)))
193 | 
194 | (defun key-quiz--command-description (cmd)
195 |   "Get a short description of command CMD.
196 | Returns nil if no description was found."
197 |   (let ((cmd-sym (intern-soft cmd)))
198 |     (when (commandp cmd-sym)
199 |       (let ((doc (documentation cmd-sym)))
200 | 	(progn
201 | 	  (when (and doc (string-match "^\\(.+?\\.\\)$" doc))
202 | 	    (match-string 1 doc)))))))
203 | 
204 | (defun key-quiz--ask ()
205 |   "Prompt the player for a key corresponding to a command.
206 | A random element from `key-quiz--keys' is chosen, and the player is
207 | shown the chosen command.  The player must then guess one of the keys
208 | corresponding to the command (as there may be more than one).
209 | Finally, return (SCORE . CORRECT-ANSWER), where SCORE is a number
210 | \(positive or negative) which should be added to `key-quiz--score',
211 | and CORRECT-ANSWER is the correct answer in case the player did not
212 | answer correctly, or nil otherwise."
213 |   (let* ((pair (if key-quiz--last-state
214 | 		   (car key-quiz--last-state)
215 | 		 (seq-random-elt key-quiz--keys)))
216 | 	 (command (cdr pair))
217 | 	 (keys (if key-quiz--last-state
218 | 		   (cdr key-quiz--last-state)
219 | 		 ;; One command may be bound to multiple keys, fetch them all.
220 | 		 (mapcar 'car (seq-filter (lambda (p)
221 | 					    (string= (cdr p) command))
222 | 					  key-quiz--keys))))
223 | 	 (all-keys (mapconcat 'identity keys " or "))
224 | 	 (best-matches nil)
225 | 	 result
226 | 	 entered-key)
227 |     (if key-quiz--last-state
228 | 	;; We are resuming, do not modify key list again.
229 | 	(setq key-quiz--last-state nil)
230 |       ;; First time using this key-command pair.
231 |       (dolist (key keys)
232 | 	;; Delete all key-command pairs that map to the same command
233 | 	;; from global key-command list. This way we don't ask for the
234 | 	;; same command more than once.
235 | 	(setf key-quiz--keys (cl-delete key key-quiz--keys
236 | 					:key #'car :test #'equal))))
237 |     (setq key-quiz--prompt-pos (point))
238 |     (insert "Enter key for command:")
239 |     (newline 2)
240 |     (insert "    " (propertize command 'font-lock-face 'key-quiz-question))
241 |     (let ((description (key-quiz--command-description command)))
242 |       (when description
243 | 	(newline)
244 | 	(insert "    " (propertize description 'font-lock-face 'italic))))
245 |     (newline 2)
246 |     (when (> (length keys) 1)
247 |       (insert (format "There are %s possible answers." (length keys)))
248 |       (newline))
249 |     (insert "Your answer: ")
250 |     (setq entered-key (key-description (read-key-sequence-vector
251 | 					"Key (RET to give up): ")))
252 |     (cond
253 |      ((string= entered-key "C-g") (throw 'end t))
254 |      ((string= entered-key "p")
255 |       ;; Save game state for resume.
256 |       (setq key-quiz--last-state (cons pair keys))
257 |       (throw 'end 'pause))
258 |      ((string= entered-key "RET") (setq entered-key "")))
259 |     (insert entered-key)
260 |     (dolist (key keys)
261 |       (let* ((matches-total (key-quiz--keys-distance entered-key key))
262 | 	     (matches (car matches-total))
263 | 	     (is-total (cdr matches-total)))
264 | 	(if (or (not best-matches)
265 | 		(< best-matches matches)
266 | 		is-total)
267 | 	    (setq result (cons (* matches key-quiz-partial-answer-score)
268 | 			       (unless is-total all-keys))
269 | 		  best-matches matches))))
270 |     result))
271 | 
272 | (defun key-quiz--ask-reverse ()
273 |   "Prompt the player for a command corresponding to a key.
274 | A random element from `key-quiz--keys' is chosen, and the player is
275 | shown the chosen key.  The player must then guess the command
276 | corresponding to the key.  Finally, return (SCORE . CORRECT-ANSWER),
277 | where SCORE is a number (positive or negative) which should be added
278 | to `key-quiz--score', and CORRECT-ANSWER is the correct answer in case
279 | the player did not answer correctly, or nil otherwise."
280 |   (let* ((pair (if key-quiz--last-state
281 | 		   (car key-quiz--last-state)
282 | 		 (seq-random-elt key-quiz--keys)))
283 | 	 (key (car pair))
284 | 	 (command (cdr pair))
285 | 	 entered-command
286 | 	 hints)
287 |     (if key-quiz--last-state
288 | 	;; We are resuming, do not modify key list again.
289 | 	(setq key-quiz--last-state nil)
290 |       ;; Delete corresponding key-command pair in global list.
291 |       (setf key-quiz--keys (cl-delete key key-quiz--keys :key #'car :test #'equal)))
292 |     ;; Randomly select hints.
293 |     (setq hints (mapcar 'cdr (cl-subseq (key-quiz--shuffle-list (copy-sequence
294 | 								 key-quiz--keys))
295 | 					0 (min (length key-quiz--keys)
296 | 					       (1- key-quiz-reverse-hints-count)))))
297 |     (when hints
298 |       (push command hints)
299 |       (key-quiz--shuffle-list hints))
300 |     (setq key-quiz--prompt-pos (point))
301 |     (insert (format "Enter command for key: %s "
302 | 		    (propertize key 'font-lock-face 'key-quiz-question)))
303 |     (newline)
304 |     (insert "Your answer: ")
305 |     ;; TODO: Handle C-g correctly
306 |     (setq entered-command (completing-read "Command (TAB to view hints): "
307 | 					   hints))
308 |     (when (string= entered-command "p")
309 |       ;; Save game state for resume.
310 |       (setq key-quiz--last-state (cons pair nil))
311 |       (throw 'end 'pause))
312 |     (insert entered-command)
313 |     (if (string= entered-command command)
314 | 	(cons (* (length (split-string key)) key-quiz-partial-answer-score)
315 | 	      nil)
316 |       (cons key-quiz-wrong-answer-score command))))
317 | 
318 | (defun key-quiz--game-loop (ask-fn)
319 |   "Iterate until `key-quiz-game-length' rounds have passed.
320 | Ask the player questions using ASK-FN, which should be a function
321 | returing (SCORE . CORRECT-ANSWER).  Return t if the game was
322 | cancelled, nil if it ended normally, and `pause' if the game was
323 | paused."
324 |   (catch 'end
325 |     (while t
326 |       (when (or (= 0 (length key-quiz--keys))
327 | 		(= key-quiz--round key-quiz-game-length))
328 | 	(throw 'end nil))
329 |       (let* ((results (funcall ask-fn))
330 | 	     (score (car results))
331 | 	     (correct-answer (cdr results)))
332 | 	(newline)
333 | 	(if correct-answer
334 | 	    (progn
335 | 	      (insert (propertize (if (< 0 score) "Almost correct!" "Wrong!")
336 | 				  'font-lock-face
337 | 				  (if (< 0 score)
338 | 				      'key-quiz-partial
339 | 				    'key-quiz-wrong)))
340 | 	      (newline)
341 | 	      (insert (format "Correct answer was: %s"
342 | 			      (propertize correct-answer
343 | 					  'font-lock-face 'key-quiz-answer))))
344 | 	  (insert (propertize "Correct!"
345 | 			      'font-lock-face 'key-quiz-correct)))
346 | 	(setq key-quiz--score (max 0 (+ key-quiz--score score))
347 | 	      key-quiz--round (1+ key-quiz--round)))
348 |       (key-quiz--insert-separator)
349 |       (newline))))
350 | 
351 | (defun key-quiz--run (ask-fn)
352 |   "Run the game.
353 | Ask the player questions using ASK-FN, which should be a function
354 | returning (SCORE . CORRECT-ANSWER)."
355 |   (let (exit-code)
356 |     (setq exit-code (key-quiz--game-loop ask-fn))
357 |     (newline 2)
358 |     (if (eq exit-code 'pause)
359 | 	(progn
360 | 	  (insert (propertize "Game paused." 'font-lock-face 'bold))
361 | 	  (newline)
362 | 	  (insert "Press 'c' to resume the game, 'r' to restart it.")
363 | 	  (message nil)) ; Clear minibuffer
364 |       (unless exit-code
365 | 	;; If game loop exited normally, update high scores.
366 | 	(gamegrid-add-score key-quiz--score-file key-quiz--score))
367 |       (insert (propertize (format "Game ended. Score: %s" key-quiz--score)
368 | 			  'font-lock-face 'bold))
369 |       (newline)
370 |       (insert "Press 'r' to start a new game, 'q' to exit."))))
371 | 
372 | (defun key-quiz--resume ()
373 |   "Resume a paused game."
374 |   (interactive)
375 |   (unless key-quiz--last-state
376 |     (error "Can't resume game: no current game"))
377 |   (let ((inhibit-read-only t))
378 |     (delete-region key-quiz--prompt-pos (point-max))
379 |     (setq key-quiz--prompt-pos nil)
380 |     (key-quiz--run (if key-quiz--game-reverse
381 | 		       'key-quiz--ask-reverse
382 | 		     'key-quiz--ask))))
383 | 
384 | (defun key-quiz--restart ()
385 |   "Restart the current game."
386 |   (interactive)
387 |   (setq key-quiz--keys (or (copy-sequence key-quiz--custom-keys)
388 | 			   (key-quiz--get-keys))
389 | 	key-quiz--score 0
390 | 	key-quiz--round 0
391 | 	key-quiz--last-state nil
392 | 	key-quiz--prompt-pos nil)
393 |   ;; Bind all keys not currently bound to a command to `ignore'. Use a
394 |   ;; copy of key-quiz-mode-map so that we can freely modify it. We do
395 |   ;; this to allow playing with keys not bound to anything.
396 |   (use-local-map (copy-keymap key-quiz-mode-map))
397 |   (dolist (key-command key-quiz--keys)
398 |     (message "%s" key-command)
399 |     (let ((key (car key-command)))
400 |       (when (integerp (lookup-key (current-local-map) (kbd key)))
401 | 	(local-set-key (kbd key) 'ignore))))
402 |   ;; Prepare buffer and start the game.
403 |   (let ((inhibit-read-only t))
404 |     (erase-buffer)
405 |     (insert (format "%s keys/commands loaded." (length key-quiz--keys)))
406 |     (newline 2)
407 |     (key-quiz--run (if key-quiz--game-reverse
408 | 		       'key-quiz--ask-reverse
409 | 		     'key-quiz--ask))))
410 | 
411 | (defun key-quiz--quit ()
412 |   "Ask the player if they want to quit the game and kill the buffer."
413 |   (interactive)
414 |   (when (yes-or-no-p "Exit game and kill buffer? ")
415 |     (kill-this-buffer)))
416 | 
417 | ;;;###autoload
418 | (defun key-quiz (&optional reverse keys)
419 |   "Play a game of Key Quiz.
420 | 
421 | Key Quiz is a game where the player must type in key sequences
422 | corresponding to different Emacs commands, chosen at random.
423 | 
424 | The game includes a variant, called 'reverse mode', where the player
425 | is given a key sequence and then must answer with the corresponding
426 | command.  This mode is activated when called interactively with a
427 | prefix argument, or when REVERSE is non-nil.
428 | 
429 | To KEYS argument can be used to specify a custom key-command list.
430 | The value of the argument must be an alist with each item having the
431 | form (KEY . COMMAND), where KEY should be a string in the format
432 | returned by commands such as `C-h k' (`describe-key'), and COMMAND
433 | should be a string representing the command bound to that key.  It is
434 | not necessary for the commands to exist, or for the keys to be
435 | actually bound to those commands.  If KEYS is omitted or nil, a
436 | key-command list will be generated from the output of running
437 | `describe-buffer-bindings' on a new buffer, set to mode
438 | `key-quiz-use-mode'.
439 | 
440 | Instructions:
441 | - Answer the questions as they are prompted.
442 | - Points are awarded for correct (or partially correct) answers.
443 | - Points are substracted for incorrect answers.
444 |   The minimum possible score is 0.
445 | - By default, 20 questions are asked per game.
446 | - Use 'p RET' to pause the game and 'c' to resume it.
447 | - Use \\[keyboard-quit] to cancel the question prompt.  Then, use 'r' to start a
448 |   new game or 'q' to kill the buffer."
449 |   (interactive "P")
450 |   (let* ((buffer (get-buffer-create "*Key Quiz*")))
451 |     (with-current-buffer buffer
452 |       (unless (derived-mode-p 'key-quiz-mode)
453 | 	(key-quiz-mode))
454 |       ;; These two variables shouldn't be modified when restarting the
455 |       ;; game.
456 |       (setq key-quiz--game-reverse reverse
457 | 	    key-quiz--custom-keys keys)
458 |       (switch-to-buffer buffer)
459 |       (key-quiz--restart))))
460 | 
461 | (provide 'key-quiz)
462 | ;;; key-quiz.el ends here
463 | 


--------------------------------------------------------------------------------
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523 | conditioned on the non-exercise of one or more of the rights that are
524 | specifically granted under this License.  You may not convey a covered
525 | work if you are a party to an arrangement with a third party that is
526 | in the business of distributing software, under which you make payment
527 | to the third party based on the extent of your activity of conveying
528 | the work, and under which the third party grants, to any of the
529 | parties who would receive the covered work from you, a discriminatory
530 | patent license (a) in connection with copies of the covered work
531 | conveyed by you (or copies made from those copies), or (b) primarily
532 | for and in connection with specific products or compilations that
533 | contain the covered work, unless you entered into that arrangement,
534 | or that patent license was granted, prior to 28 March 2007.
535 | 
536 |   Nothing in this License shall be construed as excluding or limiting
537 | any implied license or other defenses to infringement that may
538 | otherwise be available to you under applicable patent law.
539 | 
540 |   12. No Surrender of Others' Freedom.
541 | 
542 |   If conditions are imposed on you (whether by court order, agreement or
543 | otherwise) that contradict the conditions of this License, they do not
544 | excuse you from the conditions of this License.  If you cannot convey a
545 | covered work so as to satisfy simultaneously your obligations under this
546 | License and any other pertinent obligations, then as a consequence you may
547 | not convey it at all.  For example, if you agree to terms that obligate you
548 | to collect a royalty for further conveying from those to whom you convey
549 | the Program, the only way you could satisfy both those terms and this
550 | License would be to refrain entirely from conveying the Program.
551 | 
552 |   13. Use with the GNU Affero General Public License.
553 | 
554 |   Notwithstanding any other provision of this License, you have
555 | permission to link or combine any covered work with a work licensed
556 | under version 3 of the GNU Affero General Public License into a single
557 | combined work, and to convey the resulting work.  The terms of this
558 | License will continue to apply to the part which is the covered work,
559 | but the special requirements of the GNU Affero General Public License,
560 | section 13, concerning interaction through a network will apply to the
561 | combination as such.
562 | 
563 |   14. Revised Versions of this License.
564 | 
565 |   The Free Software Foundation may publish revised and/or new versions of
566 | the GNU General Public License from time to time.  Such new versions will
567 | be similar in spirit to the present version, but may differ in detail to
568 | address new problems or concerns.
569 | 
570 |   Each version is given a distinguishing version number.  If the
571 | Program specifies that a certain numbered version of the GNU General
572 | Public License "or any later version" applies to it, you have the
573 | option of following the terms and conditions either of that numbered
574 | version or of any later version published by the Free Software
575 | Foundation.  If the Program does not specify a version number of the
576 | GNU General Public License, you may choose any version ever published
577 | by the Free Software Foundation.
578 | 
579 |   If the Program specifies that a proxy can decide which future
580 | versions of the GNU General Public License can be used, that proxy's
581 | public statement of acceptance of a version permanently authorizes you
582 | to choose that version for the Program.
583 | 
584 |   Later license versions may give you additional or different
585 | permissions.  However, no additional obligations are imposed on any
586 | author or copyright holder as a result of your choosing to follow a
587 | later version.
588 | 
589 |   15. Disclaimer of Warranty.
590 | 
591 |   THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
592 | APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
593 | HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
594 | OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
595 | THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
596 | PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
597 | IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
598 | ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
599 | 
600 |   16. Limitation of Liability.
601 | 
602 |   IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
603 | WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
604 | THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
605 | GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
606 | USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
607 | DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
608 | PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
609 | EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
610 | SUCH DAMAGES.
611 | 
612 |   17. Interpretation of Sections 15 and 16.
613 | 
614 |   If the disclaimer of warranty and limitation of liability provided
615 | above cannot be given local legal effect according to their terms,
616 | reviewing courts shall apply local law that most closely approximates
617 | an absolute waiver of all civil liability in connection with the
618 | Program, unless a warranty or assumption of liability accompanies a
619 | copy of the Program in return for a fee.
620 | 
621 |                      END OF TERMS AND CONDITIONS
622 | 
623 |             How to Apply These Terms to Your New Programs
624 | 
625 |   If you develop a new program, and you want it to be of the greatest
626 | possible use to the public, the best way to achieve this is to make it
627 | free software which everyone can redistribute and change under these terms.
628 | 
629 |   To do so, attach the following notices to the program.  It is safest
630 | to attach them to the start of each source file to most effectively
631 | state the exclusion of warranty; and each file should have at least
632 | the "copyright" line and a pointer to where the full notice is found.
633 | 
634 |     <one line to give the program's name and a brief idea of what it does.>
635 |     Copyright (C) <year>  <name of author>
636 | 
637 |     This program is free software: you can redistribute it and/or modify
638 |     it under the terms of the GNU General Public License as published by
639 |     the Free Software Foundation, either version 3 of the License, or
640 |     (at your option) any later version.
641 | 
642 |     This program is distributed in the hope that it will be useful,
643 |     but WITHOUT ANY WARRANTY; without even the implied warranty of
644 |     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
645 |     GNU General Public License for more details.
646 | 
647 |     You should have received a copy of the GNU General Public License
648 |     along with this program.  If not, see <https://www.gnu.org/licenses/>.
649 | 
650 | Also add information on how to contact you by electronic and paper mail.
651 | 
652 |   If the program does terminal interaction, make it output a short
653 | notice like this when it starts in an interactive mode:
654 | 
655 |     <program>  Copyright (C) <year>  <name of author>
656 |     This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
657 |     This is free software, and you are welcome to redistribute it
658 |     under certain conditions; type `show c' for details.
659 | 
660 | The hypothetical commands `show w' and `show c' should show the appropriate
661 | parts of the General Public License.  Of course, your program's commands
662 | might be different; for a GUI interface, you would use an "about box".
663 | 
664 |   You should also get your employer (if you work as a programmer) or school,
665 | if any, to sign a "copyright disclaimer" for the program, if necessary.
666 | For more information on this, and how to apply and follow the GNU GPL, see
667 | <https://www.gnu.org/licenses/>.
668 | 
669 |   The GNU General Public License does not permit incorporating your program
670 | into proprietary programs.  If your program is a subroutine library, you
671 | may consider it more useful to permit linking proprietary applications with
672 | the library.  If this is what you want to do, use the GNU Lesser General
673 | Public License instead of this License.  But first, please read
674 | <https://www.gnu.org/licenses/why-not-lgpl.html>.
675 | 


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