lisp/tutorial.el

   1 ;;; tutorial.el --- tutorial for Emacs
   2
   3 ;; Copyright (C) 2006-2015 Free Software Foundation, Inc.
   4
   5 ;; Maintainer: emacs-devel@gnu.org
   6 ;; Keywords: help, internal
   7 ;; Package: emacs
   8
   9 ;; This file is part of GNU Emacs.
  10
  11 ;; GNU Emacs 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 ;; GNU Emacs 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 GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  23
  24 ;;; Commentary:
  25
  26 ;; Code for running the Emacs tutorial.
  27
  28 ;;; History:
  29
  30 ;; File was created 2006-09.
  31
  32 ;;; Code:
  33
  34 (require 'help-mode) ;; for function help-buffer
  35
  36 (defface tutorial-warning-face
  37   '((t :inherit font-lock-warning-face))
  38   "Face used to highlight warnings in the tutorial."
  39   :group 'help)
  40
  41 (defvar tutorial--point-before-chkeys 0
  42   "Point before display of key changes.")
  43 (make-variable-buffer-local 'tutorial--point-before-chkeys)
  44
  45 (defvar tutorial--point-after-chkeys 0
  46   "Point after display of key changes.")
  47 (make-variable-buffer-local 'tutorial--point-after-chkeys)
  48
  49 (defvar tutorial--lang nil
  50   "Tutorial language.")
  51 (make-variable-buffer-local 'tutorial--lang)
  52
  53 (defun tutorial--describe-nonstandard-key (value)
  54   "Give more information about a changed key binding.
  55 This is used in `help-with-tutorial'.  The information includes
  56 the key sequence that no longer has a default binding, the
  57 default binding and the current binding.  It also tells in what
  58 keymap the new binding has been done and how to access the
  59 function in the default binding from the keyboard.
  60
  61 For `cua-mode' key bindings that try to combine CUA key bindings
  62 with default Emacs bindings information about this is shown.
  63
  64 VALUE should have either of these formats:
  65
  66   \(cua-mode)
  67   \(current-binding KEY-FUN DEF-FUN KEY WHERE)
  68
  69 Where
  70   KEY         is a key sequence whose standard binding has been changed
  71   KEY-FUN     is the actual binding for KEY
  72   DEF-FUN     is the standard binding of KEY
  73   WHERE       is a text describing the key sequences to which DEF-FUN is
  74               bound now (or, if it is remapped, a key sequence
  75               for the function it is remapped to)"
  76   (with-output-to-temp-buffer (help-buffer)
  77     (help-setup-xref (list #'tutorial--describe-nonstandard-key value)
  78                      (called-interactively-p 'interactive))
  79     (with-current-buffer (help-buffer)
  80       (insert
  81        "Your Emacs customizations override the default binding for this key:"
  82        "\n\n")
  83       (let ((inhibit-read-only t))
  84         (cond
  85          ((eq (car value) 'cua-mode)
  86           (insert
  87            "CUA mode is enabled.
  88
  89 When CUA mode is enabled, you can use C-z, C-x, C-c, and C-v to
  90 undo, cut, copy, and paste in addition to the normal Emacs
  91 bindings.  The C-x and C-c keys only do cut and copy when the
  92 region is active, so in most cases, they do not conflict with the
  93 normal function of these prefix keys.
  94
  95 If you really need to perform a command which starts with one of
  96 the prefix keys even when the region is active, you have three
  97 options:
  98 - press the prefix key twice very quickly (within 0.2 seconds),
  99 - press the prefix key and the following key within 0.2 seconds, or
 100 - use the SHIFT key with the prefix key, i.e. C-S-x or C-S-c."))
 101          ((eq (car value) 'current-binding)
 102           (let ((cb    (nth 1 value))
 103                 (db    (nth 2 value))
 104                 (key   (nth 3 value))
 105                 (where (nth 4 value))
 106                 map
 107                 (maps (current-active-maps))
 108                 mapsym)
 109             ;; Look at the currently active keymaps and try to find
 110             ;; first the keymap where the current binding occurs:
 111             (while maps
 112               (let* ((m (car maps))
 113                      (mb (lookup-key m key t)))
 114                 (setq maps (cdr maps))
 115                 (when (eq mb cb)
 116                   (setq map m)
 117                   (setq maps nil))))
 118             ;; Now, if a keymap was found we must found the symbol
 119             ;; name for it to display to the user.  This can not
 120             ;; always be found since all keymaps does not have a
 121             ;; symbol pointing to them, but here they should have
 122             ;; that:
 123             (when map
 124               (mapatoms (lambda (s)
 125                           (and
 126                            ;; If not already found
 127                            (not mapsym)
 128                            ;; and if s is a keymap
 129                            (and (boundp s)
 130                                 (keymapp (symbol-value s)))
 131                            ;; and not the local symbol map
 132                            (not (eq s 'map))
 133                            ;; and the value of s is map
 134                            (eq map (symbol-value s))
 135                            ;; then save this value in mapsym
 136                            (setq mapsym s)))))
 137             (insert
 138              (format
 139               "The default Emacs binding for the key %s is the command ‘%s’.  "
 140               (key-description key)
 141               db))
 142             (insert "However, your customizations have "
 143                     (if cb
 144                         (format-message "rebound it to the command ‘%s’" cb)
 145                       "unbound it"))
 146             (insert ".")
 147             (when mapsym
 148               (insert "  (For the more advanced user:"
 149                       (format-message
 150                        " This binding is in the keymap ‘%s’.)" mapsym)))
 151             (if (string= where "")
 152                 (unless (keymapp db)
 153                   (insert "\n\nYou can use M-x "
 154                           (format "%s" db)
 155                           " RET instead."))
 156               (insert "\n\nWith your current key bindings"
 157                       " you can use "
 158                       (if (string-match-p "^the .*menus?$" where)
 159                           ""
 160                         "the key")
 161                       where
 162                       (format-message " to get the function ‘%s’." db))))
 163           (fill-region (point-min) (point)))))
 164       (help-print-return-message))))
 165
 166 (defun tutorial--sort-keys (left right)
 167   "Sort predicate for use with `tutorial--default-keys'.
 168 This is a predicate function to `sort'.
 169
 170 The sorting is for presentation purpose only and is done on the
 171 key sequence.
 172
 173 LEFT and RIGHT are the elements to compare."
 174   (let ((x (append (cadr left)  nil))
 175         (y (append (cadr right) nil)))
 176     ;; Skip the front part of the key sequences if they are equal:
 177     (while (and x y
 178                 (listp x) (listp y)
 179                 (equal (car x) (car y)))
 180       (setq x (cdr x))
 181       (setq y (cdr y)))
 182     ;; Try to make a comparison that is useful for presentation (this
 183     ;; could be made nicer perhaps):
 184     (let ((cx (car x))
 185           (cy (car y)))
 186       ;;(message "x=%s, y=%s;;;; cx=%s, cy=%s" x y cx cy)
 187       (cond
 188        ;; Lists? Then call this again
 189        ((and cx cy
 190              (listp cx)
 191              (listp cy))
 192         (tutorial--sort-keys cx cy))
 193        ;; Are both numbers? Then just compare them
 194        ((and (wholenump cx)
 195              (wholenump cy))
 196         (> cx cy))
 197        ;; Is one of them a number? Let that be bigger then.
 198        ((wholenump cx)
 199         t)
 200        ((wholenump cy)
 201         nil)
 202        ;; Are both symbols? Compare the names then.
 203        ((and (symbolp cx)
 204              (symbolp cy))
 205         (string< (symbol-name cy)
 206                  (symbol-name cx)))))))
 207
 208 (defconst tutorial--default-keys
 209   ;; On window system, `suspend-emacs' is replaced in the default keymap.
 210   (let* ((suspend-emacs 'suspend-frame)
 211          (default-keys
 212            ;; The first few are not mentioned but are basic:
 213            `((ESC-prefix [27])
 214              (Control-X-prefix [?\C-x])
 215              (mode-specific-command-prefix [?\C-c])
 216              (save-buffers-kill-terminal [?\C-x ?\C-c])
 217
 218              ;; * SUMMARY
 219              (scroll-up-command [?\C-v])
 220              (scroll-down-command [?\M-v])
 221              (recenter-top-bottom [?\C-l])
 222
 223              ;; * BASIC CURSOR CONTROL
 224              (forward-char [?\C-f])
 225              (backward-char [?\C-b])
 226              (forward-word [?\M-f])
 227              (backward-word [?\M-b])
 228              (next-line [?\C-n])
 229              (previous-line [?\C-p])
 230              (move-beginning-of-line [?\C-a])
 231              (move-end-of-line [?\C-e])
 232              (backward-sentence [?\M-a])
 233              (forward-sentence [?\M-e])
 234              (newline "\r")
 235              (beginning-of-buffer [?\M-<])
 236              (end-of-buffer [?\M->])
 237              (universal-argument [?\C-u])
 238
 239              ;; * WHEN EMACS IS HUNG
 240              (keyboard-quit [?\C-g])
 241
 242              ;; * DISABLED COMMANDS
 243              (downcase-region [?\C-x ?\C-l])
 244
 245              ;; * WINDOWS
 246              (delete-other-windows [?\C-x ?1])
 247              ;; C-u 0 C-l
 248              ;; Type CONTROL-h k CONTROL-f.
 249
 250              ;; * INSERTING AND DELETING
 251              ;; C-u 8 * to insert ********.
 252              (delete-backward-char "\d")
 253              (delete-char [?\C-d])
 254              (backward-kill-word [?\M-\d])
 255              (kill-word [?\M-d])
 256              (kill-line [?\C-k])
 257              (kill-sentence [?\M-k])
 258              (set-mark-command [?\C-@])
 259              (set-mark-command [?\C- ])
 260              (kill-region [?\C-w])
 261              (yank [?\C-y])
 262              (yank-pop [?\M-y])
 263
 264              ;; * UNDO
 265              (undo [?\C-x ?u])
 266
 267              ;; * FILES
 268              (find-file [?\C-x ?\C-f])
 269              (save-buffer [?\C-x ?\C-s])
 270
 271              ;; * BUFFERS
 272              (list-buffers [?\C-x ?\C-b])
 273              (switch-to-buffer [?\C-x ?b])
 274              (save-some-buffers [?\C-x ?s])
 275
 276              ;; * EXTENDING THE COMMAND SET
 277              ;; C-x     Character eXtend.  Followed by one character.
 278              (execute-extended-command [?\M-x])
 279              ;; C-x C-f         Find file
 280              ;; C-x C-s         Save file
 281              ;; C-x s           Save some buffers
 282              ;; C-x C-b         List buffers
 283              ;; C-x b           Switch buffer
 284              ;; C-x C-c         Quit Emacs
 285              ;; C-x 1           Delete all but one window
 286              ;; C-x u           Undo
 287
 288              ;; * MODE LINE
 289              (describe-mode [?\C-h ?m])
 290              (set-fill-column [?\C-x ?f])
 291              (fill-paragraph [?\M-q])
 292
 293              ;; * SEARCHING
 294              (isearch-forward [?\C-s])
 295              (isearch-backward [?\C-r])
 296
 297              ;; * MULTIPLE WINDOWS
 298              (split-window-below [?\C-x ?2])
 299              (scroll-other-window [?\C-\M-v])
 300              (other-window [?\C-x ?o])
 301              (find-file-other-window [?\C-x ?4 ?\C-f])
 302
 303              ;; * RECURSIVE EDITING LEVELS
 304              (keyboard-escape-quit [27 27 27])
 305
 306              ;; * GETTING MORE HELP
 307              ;; The most basic HELP feature is C-h c
 308              (describe-key-briefly [?\C-h ?c])
 309              (describe-key [?\C-h ?k])
 310
 311              ;; * MORE FEATURES
 312              ;; F10
 313
 314              ;; * CONCLUSION
 315              ;;(iconify-or-deiconify-frame [?\C-z])
 316              (,suspend-emacs [?\C-z]))))
 317     (sort default-keys 'tutorial--sort-keys))
 318   "Default Emacs key bindings that the tutorial depends on.")
 319
 320 (defun tutorial--detailed-help (button)
 321   "Give detailed help about changed keys."
 322   (with-output-to-temp-buffer (help-buffer)
 323     (help-setup-xref (list #'tutorial--detailed-help button)
 324                      (called-interactively-p 'interactive))
 325     (with-current-buffer (help-buffer)
 326       (let* ((tutorial-buffer  (button-get button 'tutorial-buffer))
 327              (explain-key-desc (button-get button 'explain-key-desc))
 328              (changed-keys (with-current-buffer tutorial-buffer
 329                              (save-excursion
 330                                (goto-char (point-min))
 331                                (tutorial--find-changed-keys
 332                                 tutorial--default-keys)))))
 333         (when changed-keys
 334           (insert
 335            "The following key bindings used in the tutorial have been changed
 336 from the Emacs default:\n\n" )
 337           (let ((frm "   %-14s %-27s %-16s\n"))
 338             (insert (format frm
 339                             "Standard Key" "Command" "In Your Emacs")))
 340           (dolist (tk changed-keys)
 341             (let* ((def-fun     (nth 1 tk))
 342                    (key         (nth 0 tk))
 343                    (def-fun-txt (nth 2 tk))
 344                    (where       (nth 3 tk))
 345                    (remark      (nth 4 tk))
 346                    (key-txt (key-description key))
 347                    (key-fun (with-current-buffer tutorial-buffer (key-binding key))))
 348               (unless (eq def-fun key-fun)
 349                 ;; Insert key binding description:
 350                 (when (string= key-txt explain-key-desc)
 351                   (put-text-property 0 (length key-txt)
 352                                      'face 'tutorial-warning-face key-txt))
 353                 (insert "   " key-txt " ")
 354                 (indent-to 18)
 355                 ;; Insert a link describing the old binding:
 356                 (insert-button def-fun-txt
 357                                'value def-fun
 358                                'action
 359                                (lambda (button) (interactive)
 360                                  (describe-function
 361                                   (button-get button 'value)))
 362                                'follow-link t)
 363                 (indent-to 45)
 364                 (when (listp where)
 365                   (setq where "list"))
 366                 ;; Tell where the old binding is now:
 367                 (insert (format " %-16s "
 368                                 (if (string= "" where)
 369                                     (format "M-x %s" def-fun-txt)
 370                                   where)))
 371                 ;; Insert a link with more information, for example
 372                 ;; current binding and keymap or information about
 373                 ;; cua-mode replacements:
 374                 (insert-button (car remark)
 375                                'action
 376                                (lambda (b) (interactive)
 377                                  (let ((value (button-get b 'value)))
 378                                    (tutorial--describe-nonstandard-key value)))
 379                                'value (cdr remark)
 380                                'follow-link t)
 381                 (insert "\n")))))
 382
 383         (insert "
 384 It is OK to change key bindings, but changed bindings do not
 385 correspond to what the tutorial says.\n\n")
 386         (help-print-return-message)))))
 387
 388 (defun tutorial--find-changed-keys (default-keys)
 389   "Find the key bindings used in the tutorial that have changed.
 390 Return a list with elements of the form
 391
 392   '(KEY DEF-FUN DEF-FUN-TXT WHERE REMARK QUIET)
 393
 394 where
 395
 396   KEY         is a key sequence whose standard binding has been changed
 397   DEF-FUN     is the standard binding of KEY
 398   DEF-FUN-TXT is a short descriptive text for DEF-FUN
 399   WHERE       is a text describing the key sequences to which DEF-FUN is
 400               bound now (or, if it is remapped, a key sequence
 401               for the function it is remapped to)
 402   REMARK      is a list with info about rebinding. It has either of
 403               these formats:
 404
 405                 \(TEXT cua-mode)
 406                 \(TEXT current-binding KEY-FUN DEF-FUN KEY WHERE)
 407
 408               Here TEXT is a link text to show to the user.  The
 409               rest of the list is used to show information when
 410               the user clicks the link.
 411
 412               KEY-FUN is the actual binding for KEY.
 413   QUIET       is t if this changed keybinding should be handled quietly.
 414               This is used by `tutorial--display-changes'."
 415   (let (changed-keys remark)
 416     ;; Look up the bindings in a Fundamental mode buffer
 417     ;; so we do not get fooled by some other major mode.
 418     (with-temp-buffer
 419       (fundamental-mode)
 420       (dolist (kdf default-keys)
 421         ;; The variables below corresponds to those with the same names
 422         ;; described in the doc string.
 423         (let* ((key     (nth 1 kdf))
 424                (def-fun (nth 0 kdf))
 425                (def-fun-txt (format "%s" def-fun))
 426                (rem-fun (command-remapping def-fun))
 427                ;; Handle prefix definitions specially
 428                ;; so that a mode that rebinds some subcommands
 429                ;; won't make it appear that the whole prefix is gone.
 430                (key-fun (if (eq def-fun 'ESC-prefix)
 431                             (lookup-key global-map [27])
 432                           (if (eq def-fun 'Control-X-prefix)
 433                               (lookup-key global-map [24])
 434                             (key-binding key))))
 435                (where (where-is-internal (if rem-fun rem-fun def-fun)))
 436                cwhere)
 437
 438           (if where
 439               (progn
 440                 (setq cwhere (car where)
 441                       where (key-description cwhere))
 442                 (when (and (< 10 (length where))
 443                            (string= (substring where 0 (length "<menu-bar>"))
 444                                     "<menu-bar>"))
 445                   (setq where
 446                         (if (and (vectorp cwhere)
 447                                  (setq cwhere (elt cwhere 1))
 448                                  (setq cwhere
 449                                        (cadr
 450                                         (assoc cwhere
 451                                                (lookup-key global-map
 452                                                            [menu-bar]))))
 453                                  (stringp cwhere))
 454                             (format-message "the ‘%s’ menu" cwhere)
 455                           "the menus"))))
 456             (setq where ""))
 457           (setq remark nil)
 458           (unless
 459               (cond ((eq key-fun def-fun)
 460                      ;; No rebinding, return t
 461                      t)
 462                     ((and key-fun
 463                           (eq key-fun (command-remapping def-fun)))
 464                      ;; Just a remapping, return t
 465                      t)
 466                     ;; cua-mode specials:
 467                     ((and cua-mode
 468                           (or (and
 469                                (equal key [?\C-v])
 470                                (eq key-fun 'cua-paste))
 471                               (and
 472                                (equal key [?\C-z])
 473                                (eq key-fun 'undo))))
 474                      (setq remark (list "cua-mode, more info" 'cua-mode))
 475                      nil)
 476                     ((and cua-mode
 477                           (or (and (eq def-fun 'ESC-prefix)
 478                                    (equal key-fun
 479                                           `(keymap
 480                                             (118 . cua-repeat-replace-region)))
 481                                    (setq def-fun-txt "\"ESC prefix\""))
 482                               (and (eq def-fun 'mode-specific-command-prefix)
 483                                    (equal key-fun
 484                                           '(keymap
 485                                             (timeout . copy-region-as-kill)))
 486                                    (setq def-fun-txt "\"C-c prefix\""))
 487                               (and (eq def-fun 'Control-X-prefix)
 488                                    (equal key-fun
 489                                           '(keymap (timeout . kill-region)))
 490                                    (setq def-fun-txt "\"C-x prefix\""))))
 491                      (setq remark (list "cua-mode replacement" 'cua-mode))
 492                      (setq where "Same key")
 493                      nil)
 494                     ;; viper-mode specials:
 495                     ((and (boundp 'viper-mode-string)
 496                           (boundp 'viper-current-state)
 497                           (eq viper-current-state 'vi-state)
 498                           (or (and (eq def-fun 'isearch-forward)
 499                                    (eq key-fun 'viper-isearch-forward))
 500                               (and (eq def-fun 'isearch-backward)
 501                                    (eq key-fun 'viper-isearch-backward))))
 502                      ;; These bindings works as the default bindings,
 503                      ;; return t
 504                      t)
 505                     ((when normal-erase-is-backspace
 506                        (or (and (equal key [C-delete])
 507                                 (equal key-fun 'kill-word))
 508                            (and (equal key [C-backspace])
 509                                 (equal key-fun 'backward-kill-word))))
 510                      ;; This is the strange handling of C-delete and
 511                      ;; C-backspace, return t
 512                      t)
 513                     (t
 514                      ;; This key has indeed been rebound. Put information
 515                      ;; in `remark' and return nil
 516                      (setq remark
 517                            (list "more info" 'current-binding
 518                                  key-fun def-fun key where))
 519                      nil))
 520             (add-to-list 'changed-keys
 521                          (list key def-fun def-fun-txt where remark nil))))))
 522     changed-keys))
 523
 524 (defun tutorial--key-description (key)
 525   (let ((desc (key-description key)))
 526     (cond ((string= "ESC" desc) "<ESC>")
 527           ((string= "RET" desc) "<Return>")
 528           ((string= "DEL" desc) "<Delback>")
 529           (t desc))))
 530
 531 (defun tutorial--display-changes ()
 532   "Display changes to some default key bindings.
 533 If some of the default key bindings that the tutorial depends on
 534 have been changed then display the changes in the tutorial buffer
 535 with some explanatory links."
 536   (let* ((changed-keys (tutorial--find-changed-keys
 537                         tutorial--default-keys))
 538          ;; Alist of element (DESC . CK) where DESC is the
 539          ;; key-description of a changed key and CK is the
 540          ;; corresponding element in `changed-keys'.
 541          (changed-keys-alist
 542           (mapcar (lambda (ck) (cons (tutorial--key-description (car ck)) ck))
 543                   changed-keys))
 544          changed-key
 545          (start (point))
 546          (case-fold-search nil)
 547          (keybindings-regexp
 548           ;; Accept either [:space:] or [:punct:] before the key
 549           ;; binding because the Hebrew tutorial uses directional
 550           ;; controls and Hebrew character maqaf, the Hebrew hyphen,
 551           ;; immediately before the binding string.
 552           (concat "\\(?:[[:space:]]\\|[[:punct:]]\\)\\("
 553                   (mapconcat (lambda (kdf) (regexp-quote
 554                                             (tutorial--key-description
 555                                              (nth 1 kdf))))
 556                              tutorial--default-keys
 557                              "\\|")
 558                   "\\)[[:punct:][:space:]]")))
 559     ;; Need the custom button face for viper buttons:
 560     (if (boundp 'viper-mode-string) (require 'cus-edit))
 561
 562     (if (or changed-keys (boundp 'viper-mode-string))
 563         (let ((head  (get-lang-string tutorial--lang 'tut-chgdhead))
 564               (head2 (get-lang-string tutorial--lang 'tut-chgdhead2)))
 565           (when (and head head2)
 566             (goto-char tutorial--point-before-chkeys)
 567             (insert head " [")
 568             (insert-button head2 'tutorial-buffer (current-buffer)
 569                            'action 'tutorial--detailed-help
 570                            'follow-link t 'face 'link)
 571             (insert "]\n\n")
 572             (add-text-properties tutorial--point-before-chkeys (point)
 573                                  '(tutorial-remark remark
 574                                    face tutorial-warning-face
 575                                    read-only t)))))
 576
 577     ;; Scan the tutorial for all key sequences.
 578     (goto-char (point-min))
 579     (while (re-search-forward keybindings-regexp (point-max) t)
 580       ;; Then highlight each rebound key sequence.
 581       ;; This avoids issuing a warning for, e.g., C-x C-b if C-b is rebound.
 582       (setq changed-key (assoc (match-string 1) changed-keys-alist))
 583       (and changed-key
 584            (not (get-text-property (match-beginning 1) 'tutorial-remark))
 585            (let* ((desc    (car changed-key))
 586                   (ck      (cdr changed-key))
 587                   (def-fun (nth 1 ck))
 588                   (where   (nth 3 ck))
 589                   s1 s2 help-string)
 590              (unless (string= where "Same key")
 591                (when (string= where "")
 592                  (setq where (format "M-x %s" def-fun)))
 593                (setq tutorial--point-after-chkeys (point-marker)
 594                      s1 (get-lang-string tutorial--lang 'tut-chgdkey)
 595                      s2 (get-lang-string tutorial--lang 'tut-chgdkey2)
 596                      help-string (and s1 s2 (format s1 desc where)))
 597                (add-text-properties (match-beginning 1) (match-end 1)
 598                                     '(face tutorial-warning-face
 599                                       tutorial-remark key-sequence))
 600                (if help-string
 601                    (if (nth 5 ck)
 602                        ;; Put help string in the tooltip.
 603                        (put-text-property (match-beginning 1) (match-end 1)
 604                                           'help-echo help-string)
 605                      ;; Put help string in the buffer.
 606                      (save-excursion
 607                        (setcar (nthcdr 5 ck) t)
 608                        (forward-line)
 609                        ;; Two or more changed keys were on the same line.
 610                        (while (eq (get-text-property (point) 'tutorial-remark)
 611                                   'remark)
 612                          (forward-line))
 613                        (setq start (point))
 614                        (insert "** " help-string " [")
 615                        (insert-button s2 'tutorial-buffer (current-buffer)
 616                                       'action 'tutorial--detailed-help
 617                                       'explain-key-desc desc 'follow-link t
 618                                       'face 'link)
 619                        (insert "] **\n")
 620                        (add-text-properties start (point)
 621                                             '(tutorial-remark remark
 622                                               rear-nonsticky t
 623                                               face tutorial-warning-face
 624                                               read-only t)))))))))))
 625
 626 (defun tutorial--saved-dir ()
 627   "Directory to which tutorials are saved."
 628   (locate-user-emacs-file "tutorial/"))
 629
 630 (defun tutorial--saved-file ()
 631   "File name in which to save tutorials."
 632   (let ((file-name tutorial--lang)
 633         (ext (file-name-extension tutorial--lang)))
 634     (when (or (not ext)
 635               (string= ext ""))
 636       (setq file-name (concat file-name ".tut")))
 637     (expand-file-name file-name (tutorial--saved-dir))))
 638
 639 (defun tutorial--remove-remarks ()
 640   "Remove the remark lines that was added to the tutorial buffer."
 641   (save-excursion
 642     (goto-char (point-min))
 643     (let (prop-start
 644           prop-end
 645           prop-val)
 646       ;; Catch the case when we already are on a remark line
 647       (while (if (get-text-property (point) 'tutorial-remark)
 648                  (setq prop-start (point))
 649                (setq prop-start (next-single-property-change (point) 'tutorial-remark)))
 650         (setq prop-end (next-single-property-change prop-start 'tutorial-remark))
 651         (setq prop-val (get-text-property prop-start 'tutorial-remark))
 652         (unless prop-end
 653           (setq prop-end (point-max)))
 654         (goto-char prop-end)
 655         (unless (eq prop-val 'key-sequence)
 656           (delete-region prop-start prop-end))))))
 657
 658 (defun tutorial--save-tutorial ()
 659   "Save the tutorial buffer.
 660 This saves the part of the tutorial before and after the area
 661 showing changed keys.  It also saves the point position and the
 662 position where the display of changed bindings was inserted."
 663   ;; This runs in a hook so protect it:
 664   (condition-case err
 665       (if (y-or-n-p "Save your position in the tutorial? ")
 666           (tutorial--save-tutorial-to (tutorial--saved-file))
 667         (message "Tutorial position not saved"))
 668     (error (message "Error saving tutorial state: %s"
 669                     (error-message-string err)))))
 670
 671 (defun tutorial--save-tutorial-to (saved-file)
 672   "Save the tutorial buffer to SAVED-FILE.
 673 See `tutorial--save-tutorial' for more information."
 674   ;; Anything to save?
 675   (when (or (buffer-modified-p)
 676             (< 1 (point)))
 677     (let ((tutorial-dir (tutorial--saved-dir))
 678           save-err)
 679       ;; The tutorial is saved in a subdirectory in the user home
 680       ;; directory. Create this subdirectory first.
 681       (unless (file-directory-p tutorial-dir)
 682         (condition-case err
 683             (make-directory tutorial-dir nil)
 684           (error (setq save-err t)
 685                  (warn "Could not create directory %s: %s" tutorial-dir
 686                        (error-message-string err)))))
 687       ;; Make sure we have that directory.
 688       (if (file-directory-p tutorial-dir)
 689           (let ((tut-point (if (= 0 tutorial--point-after-chkeys)
 690                                ;; No info about changed keys is
 691                                ;; displayed.
 692                                (point)
 693                              (if (< (point) tutorial--point-after-chkeys)
 694                                  (- (point))
 695                                (- (point) tutorial--point-after-chkeys))))
 696                 (old-point (point))
 697                 ;; Use a special undo list so that we easily can undo
 698                 ;; the changes we make to the tutorial buffer.  This is
 699                 ;; currently not needed since we now delete the buffer
 700                 ;; after saving, but kept for possible future use of
 701                 ;; this function.
 702                 buffer-undo-list
 703                 (inhibit-read-only t))
 704             ;; Delete the area displaying info about changed keys.
 705             ;;             (when (< 0 tutorial--point-after-chkeys)
 706             ;;               (delete-region tutorial--point-before-chkeys
 707             ;;                              tutorial--point-after-chkeys))
 708             ;; Delete the remarks:
 709             (tutorial--remove-remarks)
 710             ;; Put the value of point first in the buffer so it will
 711             ;; be saved with the tutorial.
 712             (goto-char (point-min))
 713             (insert (number-to-string tut-point)
 714                     "\n"
 715                     (number-to-string (marker-position
 716                                        tutorial--point-before-chkeys))
 717                     "\n")
 718             (condition-case err
 719                 (write-region nil nil saved-file)
 720               (error (setq save-err t)
 721                      (warn "Could not save tutorial to %s: %s"
 722                            saved-file
 723                            (error-message-string err))))
 724             ;; An error is raised here?? Is this a bug?
 725             (ignore-errors (undo-only))
 726             ;; Restore point
 727             (goto-char old-point)
 728             (if save-err
 729                 (message "Could not save tutorial state.")
 730               (message "Saved tutorial state.")))
 731         (message "Can't save tutorial: %s is not a directory"
 732                  tutorial-dir)))))
 733
 734
 735 ;;;###autoload
 736 (defun help-with-tutorial (&optional arg dont-ask-for-revert)
 737   "Select the Emacs learn-by-doing tutorial.
 738 If there is a tutorial version written in the language
 739 of the selected language environment, that version is used.
 740 If there's no tutorial in that language, `TUTORIAL' is selected.
 741 With ARG, you are asked to choose which language.
 742 If DONT-ASK-FOR-REVERT is non-nil the buffer is reverted without
 743 any question when restarting the tutorial.
 744
 745 If any of the standard Emacs key bindings that are used in the
 746 tutorial have been changed then an explanatory note about this is
 747 shown in the beginning of the tutorial buffer.
 748
 749 When the tutorial buffer is killed the content and the point
 750 position in the buffer is saved so that the tutorial may be
 751 resumed later."
 752   (interactive "P")
 753   (if (boundp 'viper-current-state)
 754       (let ((prompt1
 755              "You can not run the Emacs tutorial directly because you have \
 756 enabled Viper.")
 757             (prompt2 "\nThere is however a Viper tutorial you can run instead.
 758 Run the Viper tutorial? "))
 759         (if (fboundp 'viper-tutorial)
 760             (if (y-or-n-p (concat prompt1 prompt2))
 761                 (progn (message "")
 762                        (funcall 'viper-tutorial 0))
 763               (message "Tutorial aborted by user"))
 764           (message prompt1)))
 765     (let* ((lang (cond
 766                   (arg
 767                    (minibuffer-with-setup-hook #'minibuffer-completion-help
 768                      (read-language-name 'tutorial "Language: " "English")))
 769                   ((get-language-info current-language-environment 'tutorial)
 770                    current-language-environment)
 771                   (t "English")))
 772            (filename (get-language-info lang 'tutorial))
 773            (tut-buf-name filename)
 774            (old-tut-buf (get-buffer tut-buf-name))
 775            (old-tut-win (when old-tut-buf (get-buffer-window old-tut-buf t)))
 776            (old-tut-is-ok (when old-tut-buf
 777                             (not (buffer-modified-p old-tut-buf))))
 778            old-tut-file
 779            (old-tut-point 1))
 780       (setq tutorial--point-after-chkeys (point-min))
 781       ;; Try to display the tutorial buffer before asking to revert it.
 782       ;; If the tutorial buffer is shown in some window make sure it is
 783       ;; selected and displayed:
 784       (if old-tut-win
 785           (raise-frame
 786            (window-frame
 787             (select-window (get-buffer-window old-tut-buf t))))
 788         ;; Else, is there an old tutorial buffer? Then display it:
 789         (when old-tut-buf
 790           (switch-to-buffer old-tut-buf)))
 791       ;; Use whole frame for tutorial
 792       (delete-other-windows)
 793       ;; If the tutorial buffer has been changed then ask if it should
 794       ;; be reverted:
 795       (when (and old-tut-buf
 796                  (not old-tut-is-ok))
 797         (setq old-tut-is-ok
 798               (if dont-ask-for-revert
 799                   nil
 800                 (not (y-or-n-p
 801                       "You have changed the Tutorial buffer.  Revert it? ")))))
 802       ;; (Re)build the tutorial buffer if it is not ok
 803       (unless old-tut-is-ok
 804         (switch-to-buffer (get-buffer-create tut-buf-name))
 805         ;; (unless old-tut-buf (text-mode))
 806         (unless lang (error "Variable lang is nil"))
 807         (setq tutorial--lang lang)
 808         (setq old-tut-file (file-exists-p (tutorial--saved-file)))
 809         (let ((inhibit-read-only t))
 810           (erase-buffer))
 811         (message "Preparing tutorial ...") (sit-for 0)
 812
 813         ;; Do not associate the tutorial buffer with a file. Instead use
 814         ;; a hook to save it when the buffer is killed.
 815         (setq buffer-auto-save-file-name nil)
 816         (add-hook 'kill-buffer-hook 'tutorial--save-tutorial nil t)
 817
 818         ;; Insert the tutorial. First offer to resume last tutorial
 819         ;; editing session.
 820         (when dont-ask-for-revert
 821           (setq old-tut-file nil))
 822         (when old-tut-file
 823           (setq old-tut-file
 824                 (y-or-n-p "Resume your last saved tutorial? ")))
 825         (if old-tut-file
 826             (progn
 827               (insert-file-contents (tutorial--saved-file))
 828               (let ((enable-local-variables :safe)
 829                     (enable-local-eval nil)
 830                     (enable-dir-local-variables nil)) ; bug#11127
 831                 (hack-local-variables))
 832               (goto-char (point-min))
 833               (setq old-tut-point
 834                     (string-to-number
 835                      (buffer-substring-no-properties
 836                       (line-beginning-position) (line-end-position))))
 837               (forward-line)
 838               (setq tutorial--point-before-chkeys
 839                     (string-to-number
 840                      (buffer-substring-no-properties
 841                       (line-beginning-position) (line-end-position))))
 842               (forward-line)
 843               (delete-region (point-min) (point))
 844               (goto-char tutorial--point-before-chkeys)
 845               (setq tutorial--point-before-chkeys (point-marker)))
 846           (insert-file-contents (expand-file-name filename tutorial-directory))
 847           (let ((enable-local-variables :safe)
 848                 (enable-local-eval nil)
 849                 (enable-dir-local-variables nil)) ; bug#11127
 850             (hack-local-variables))
 851           (forward-line)
 852           (setq tutorial--point-before-chkeys (point-marker)))
 853
 854         (tutorial--display-changes)
 855
 856         ;; Clear message:
 857         (unless dont-ask-for-revert
 858           (message "") (sit-for 0))
 859
 860
 861         (if old-tut-file
 862             ;; Just move to old point in saved tutorial.
 863             (let ((old-point
 864                    (if (> 0 old-tut-point)
 865                        (- old-tut-point)
 866                      (+ old-tut-point tutorial--point-after-chkeys))))
 867               (when (< old-point 1)
 868                 (setq old-point 1))
 869               (goto-char old-point))
 870           ;; Delete the arch-tag line, so as not to confuse readers.
 871           (goto-char (point-max))
 872           (if (search-backward ";;; arch-tag: " nil t)
 873               (delete-region (point) (point-max)))
 874           (goto-char (point-min))
 875           (search-forward "\n<<")
 876           (beginning-of-line)
 877           ;; Convert the <<...>> line to the proper [...] line,
 878           ;; or just delete the <<...>> line if a [...] line follows.
 879           (cond ((save-excursion
 880                    (forward-line 1)
 881                    (looking-at-p "\\["))
 882                  (delete-region (point) (progn (forward-line 1) (point))))
 883                 ((looking-at "<<Blank lines inserted.*>>")
 884                  (replace-match "[Middle of page left blank for didactic purposes.   Text continues below]"))
 885                 (t
 886                  (looking-at "<<")
 887                  (replace-match "[")
 888                  (search-forward ">>")
 889                  (replace-match "]")))
 890           (beginning-of-line)
 891           ;; FIXME: if the window is not tall, and especially if the
 892           ;; big red "NOTICE: The main purpose..." text has been
 893           ;; inserted at the start of the buffer, the "type C-v to
 894           ;; move to the next screen" might not be visible on the
 895           ;; first screen (n < 0).  How will the novice know what to do?
 896           (let ((n (- (window-height)
 897                       (count-lines (point-min) (point))
 898                       6)))
 899             (if (< n 8)
 900                 (progn
 901                   ;; For a short gap, we don't need the [...] line,
 902                   ;; so delete it.
 903                   (delete-region (point) (progn (end-of-line) (point)))
 904                   (if (> n 0) (newline n)))
 905               ;; Some people get confused by the large gap.
 906               (newline (/ n 2))
 907
 908               ;; Skip the [...] line (don't delete it).
 909               (forward-line 1)
 910               (newline (- n (/ n 2)))))
 911           (goto-char (point-min)))
 912         (setq buffer-undo-list nil)
 913         (set-buffer-modified-p nil)))))
 914
 915
 916 ;; Below is some attempt to handle language specific strings. These
 917 ;; are currently only used in the tutorial.
 918
 919 (defconst lang-strings
 920   '(("English" .
 921      ((tut-chgdkey . "%s has been rebound, but you can use %s instead")
 922       (tut-chgdkey2 . "More")
 923       (tut-chgdhead . "
 924  NOTICE: The main purpose of the Emacs tutorial is to teach you
 925  the most important standard Emacs commands (key bindings).
 926  However, your Emacs has been customized by changing some of
 927  these basic editing commands, so it doesn't correspond to the
 928  tutorial.  We have inserted colored notices where the altered
 929  commands have been introduced.")
 930       (tut-chgdhead2 . "More"))))
 931   "Language specific strings for Emacs.
 932 This is an association list with the keys equal to the strings
 933 that can be returned by `read-language-name'.  The elements in
 934 the list are themselves association lists with keys that are
 935 string ids and values that are the language specific strings.
 936
 937 See `get-lang-string' for more information.")
 938
 939 (defun get-lang-string (lang stringid &optional no-eng-fallback)
 940   "Get a language specific string for Emacs.
 941 In certain places Emacs can replace a string shown to the user with
 942 a language specific string.  This function retrieves such strings.
 943
 944 LANG is the language specification.  It should be one of those
 945 strings that can be returned by `read-language-name'.  STRINGID
 946 is a symbol that specifies the string to retrieve.
 947
 948 If no string is found for STRINGID in the chosen language then
 949 the English string is returned unless NO-ENG-FALLBACK is non-nil.
 950
 951 See `lang-strings' for more information.
 952
 953 Currently this feature is only used in `help-with-tutorial'."
 954   (let ((my-lang-strings (assoc lang lang-strings))
 955         (found-string))
 956     (when my-lang-strings
 957       (let ((entry (assoc stringid (cdr my-lang-strings))))
 958         (when entry
 959           (setq found-string (cdr entry)))))
 960     ;; Fallback to English strings
 961     (unless (or found-string
 962                 no-eng-fallback)
 963       (setq found-string (get-lang-string "English" stringid t)))
 964     found-string))
 965
 966 ;;(get-lang-string "English" 'tut-chgdkey)
 967
 968 (provide 'tutorial)
 969
 970 ;;; tutorial.el ends here