This first demonstration of emacs accompanies
http://pages.stat.wisc.edu/~jgillett/DSCP/emacs/emacs.html. It covers
the lines that are not crossed out. (I wrote this file in response to
student requests, but I do not really intend that students would read
it, as any little mistake makes it impossible to follow. Instead,
practice with the various emacs commands, possibly guided a little by
this file.)

----------------------------------------------------------------------
Make emacs folder:
- cd          # change to home directory
- mkdir emacs # create new directory "emacs"
- cd emacs    # change to emacs diretory

Save data.txt to emacs folder:
- Run wget https://pages.stat.wisc.edu/~jgillett/DSCP/emacs/data.txt

Practice with emacs:
- Start/Stop
  - start emacs:
    - login to public02, public03, or public04
      (i.e. public02.stat.wisc.edu, etc.)
    - emacs -nw ("-nw" = "--no-window-system": run emacs in Terminal window)
  - exit: C-x C-c
- Files
  - read a file into emacs: C-x C-f ~/emacs/data.txt Enter
    ("~" = "home directory")
    It's easier to use TAB to complete names:
    C-x C-f ~/e TAB TAB Enter
  - create a new file: C-x C-f junk.txt Enter
  - insert a file: C-x i d TAB Enter
  - save: C-x C-s
  - save as: C-x C-w junk2.txt (sanity check: use GUI to view emacs folder)
- Cursor Motion
  - forward, next, backward, previous (3 times each):
    C-f C-f C-f C-n C-n C-n C-b C-b C-b C-p C-p C-p
- Cut, Copy, Paste
  - delete current character (after moving forward 2): C-f C-f C-d
  - delete previous character: Backspace
  - kill to end of line (do it a second time to get newline): C-k C-k
  - set mark; "region" is between invisible "mark" and "point" (cursor)
    (after 7 forwards): C-f (7 times to "S") C-SPACE 
  - kill region (after down and left 3 to "J"): C-n C-b C-b C-b C-w
  - copy region (after setting mark and down to "J"): C-SPACE C-n M-w
  - yank back last thing killed (after down to end): C-n C-y
- Formatting
  - use wget to download tiny.R to ~/emacs
  - open tiny.R: C-x C-f tiny.R Enter
  - move to line 4: C-n C-n C-n C-n
  - indent current line: TAB
  - indent buffer: M-< (jump to top), C-SPACE (set mark),
    M-> (jump to bottom), M-x indent-region Enter
  - use wget to download sifting.txt to ~/emacs
  - open sifting.txt: C-x C-f s TAB Enter
  - fill paragraph: M-q
- Buffers
  - exit (for a clean slate) C-x C-c
  - find (open) a few files:
    - open data.txt: C-x C-f ~/D TAB e TAB d TAB Enter
    - open tiny.R: C-x C-f t TAB Enter
    - open sifting.txt: C-x C-f s TAB Enter
  - list buffers: C-x C-b
  - visit a buffer from the buffer list: SPACE
  - close a buffer: C-x k
  - go to shell buffer: C-z (we'll use this command line soon)
- Error Recovery
  - abort partially typed or executing command: e.g. start to open file, abort: C-x C-f C-g
  - undo an unwanted change: e.g. open tiny.R, delete two characters and 3rd line, undo:
    C-x C-f t TAB Enter
    C-d C-d C-n C-n C-k C-k C-/ C-/ C-/
- The Minibuffer
  - complete as much as possible: e.g. open tiny.R: C-x C-f TAB t TAB Enter
  - Type C-x ESC ESC to repeat the last command that used the
    minibuffer. Then the following keys are defined:
    - previous minibuffer command: M-p
    - next minibuffer command: M-n
- Incremental Search
  - find tiny.R: C-x C-f t TAB Enter
  - search forward for "(": C-s (
  - repeat search: C-s C-s C-s C-s C-s C-s
  - exit search: Enter
  - search backward for ")": C-r ) C-r C-r
  - exit search: Enter
- Query Replace
  - find data.txt: C-x C-f d TAB Enter
  - interactively replace text ("3" with "THREE"):
    M-% 3 Enter THREE Enter
    y y y n y
  - undo 4 times: C-/ C-/ C-/ C-/
  - repeat last command (above): C-x ESC ESC, change "THREE" to "_THREE_", Enter
- Directory Editor to list and manage files
  - find directory ("." is shorthand for "current directory"): C-x C-f .
  - help with directory-editor mode: ?
  - delete (rather, mark for deleting) 2nd file: C-n d
  - expunge (delete files marked for deleting): x y
  - find: f
  - rename: R tiny.R.save
  - copy: C tiny.R Enter
  - create directory: + backup Enter
  - copy tiny.R.save to backup directory (once on tiny.R.save line): C b TAB Enter
- Help
  - help: M-x help
  - tutorial: M-x help Enter t