emacs.txt

Writing A Spotify Client in 16 Minutes
    https://www.youtube.com/watch?v=XjKtkEMUYGc

http://www.masteringemacs.org/

http://www.emacswiki.org/emacs/Reference_Sheet_by_Aaron_Hawley

very good explanation of (autoload):
    http://www.lunaryorn.com/2014/07/02/autoloads-in-emacs-lisp.html

C-h m           available major/minor modes and bindings
C-h k           show the functions bound to a key sequence
C-h f           show the key sequence(s) bound to a function
M-x occur       regex-based outline!

TERMINAL
========
synopsis of shell and terminal modes included in Emacs
    https://lukeshu.com/blog/emacs-shells.html
tips, env vars
    http://snarfed.org/why_i_run_shells_inside_emacs


MODE HOOKS
==========
Mode hooks are like Vim ftplugins: allows you to execute arbitrary elisp for modes.
For example:
    (add-hook 'prog-mode-hook 'linum-on)
`prog-mode-hook` is the generic hook that most programming modes are derived
from (i.e. emacs-lisp-mode, c-mode....). If you add a function to
`prog-mode-hook`, that function is executed in every mode derived from
`prog-mode`. In this case, linum will be activated in every programming mode,
but not modes like help-mode or dired-mode. So, file-types are _loosely_
associated with major modes. Major modes are associated with _content_. I said
"loosely" because you do not necessary use the code of a major mode with a file
of a particular type; you can use it in any buffer. For example, you can
activate `asm-mode` on a buffer that holds the output of the command `objdump`
to have really nice highlighting and features of asm-mode. For example, you may
want to enable smerge-mode in a buffer with merge conflict:
    (defun enable-smerge ()
      (save-excursion
        (goto-char (point-min))
        (when (re-search-forward "^<<<<<<< " nil t) ; search for conflict marking
          (smerge-mode 1))))
    (add-hook 'find-file-hook 'enable-smerge t)


EMACS LISP
==========
[video] intro to emacs lisp (and ERC): http://emacsnyc.org/videos.html#2014-04

show results in buffer, a la Light table:
    <C-j> eval-print-last-sexp

difference between define-key, evil-define-key:
    (define-key evil-motion-state-local-map "a" 'foo)
        ;binds "a" in the CURRENT BUFFER for ALL MODES
    (evil-define-key 'motion foo-mode-map "a" 'foo)
        ;binds "a" for ALL BUFFERS in ONLY THE SPECIFIED MODE

'foo  means (quote foo)
#'foo means (function foo)
    - special form that returns a function-object without evaluating it
    - converted into a closure if lexical binding is enabled
    - in practice, you will probably never need #' in elisp
    http://stackoverflow.com/questions/25275842/does-function-serve-any-purpose-in-emacs

;; macroexpand expands the form until a non-macro is found, but
;; it does _not_ inspect _sub_expressions in the resolved macro.
;; http://www.chemie.fu-berlin.de/chemnet/use/info/elisp/elisp_13.html
(defmacro inc (var)
    (list 'setq var (list '1+ var)))
    ;; => inc

(macroexpand '(inc r))
    ;; => (setq r (1+ r))

(defmacro inc2 (var1 var2)
    (list 'progn (list 'inc var1) (list 'inc var2)))
    ;; => inc2

(macroexpand '(inc2 r s))
    ;; => (progn (inc r) (inc s))