(Stupid) Useful Emacs Tricks?

Count Fenring writes "Since the Vi version of this question was both interesting and popular, let's hear from the other end of the spectrum. What are your favorite tricks, macros, extensions, and techniques for any of the various Emacs? Myself, I like 'M-x dunnet' ;-)"

XKCD

C-X M-C M-butterfly

grep and emacs integration

Of all the Elisp I've written this grep is what I most miss when I use a coworker's environment.

(defun my-grep ()
  "grep the whole directory for something defaults to term at cursor position"
  (interactive)
  (setq default (thing-at-point 'symbol))
  (setq needle (or (read-string (concat "grep for <" default "> ")) default))
  (setq needle (if (equal needle "") default needle))
  (grep (concat "egrep -s -i -n " needle " * /dev/null")))
(global-set-key "\C-x." 'my-grep)
(global-set-key [f8] 'next-error)

Re:grep and emacs integration

Like M-x rgrep? It's builtin now.

Re:grep and emacs integration

Isn't that usually spelled

M-| wc

Meta-pipe is a great one -- it's "pipe region to external command" (M-x shell-command-on-region)

Some favorites

(global-set-key (kbd "C-c c") 'comment-dwim)

C-c c to either comment out a region or uncomment it depending on context. Lovely feature.

(global-set-key "\M-g" 'goto-line)

M-g to go to specified line in buffer. Useful for emacs 21.x users where the keybinding is not yet standard.

(menu-bar-mode nil) (scroll-bar-mode nil) (tool-bar-mode nil)

Gets rid of the ugly TK widgets.

(iswitchb-mode t)

Superboosts C-x b.

(global-set-key "\C-z" 'undo)

The normal binding for C-z is suspend-emacs but having it bound as undo is much more useful imo.

editing over ssh

Always handy when doing a bit of work remotely. Put:

(require 'tramp)
(setq tramp-default-method "scp")

in one's .emacs file. Then open remote files with:

/username@host:remote_path

Outlines w/ org-mode

I've recently discovered and almost instantly become a fan of org-mode, which is a great outlining tool (including folding, numbering, and other similar things you'd probably expect).

It's also good for lists of things to do, schedules, deadlines, and related stuff. It uses its own really simple markup langauge (similar to trac wiki), but you can include LaTeX and HTML inline.

It comes with exporters to HTML and LaTeX (and iCal for date stuff). You can also put tables inline, and the table editor is excellent for simple tables.

I use it every day for my list of things to do, and use it regularly for outlining text documents, pseudocode, and meeting notes.

AUCTeX with preview-latex

When writing scientific papers in LaTeX, there's nothing else that comes close to the power of AUCTeX with preview-latex http://www.gnu.org/software/auctex/preview-latex.html [gnu.org]. It allows you to view typeset equations inline with the rest of the document, but on moving the cursor into an equation, shows the original code. After editing, one brief command, and the new equation is typeset and displayed.

Edit files from anywhere w/ tramp

One of my favorite emacsisms a long time ago was ange-ftp, and the modern descendant, tramp, is one of my current faves. It lets you edit remote files over lots of protocols, including: ssh, scp, ftp, rsync, ftp, and smb.

Most emacs stuff works transparently, like dired and archive browsing. When you edit a file and save it, it's automatically put back on the remote machine. I have had trouble with psvn, but that's about the only thing that I kinda expected to work that didn't.

If you edit remote files and you use emacs, you want to start using this.

there's a whole wiki to answer this question

Take a look to http://www.emacswiki.org/emacs/EmacsNiftyTricks [emacswiki.org].

some of mine

1)First, ESS, Emacs speaks statistics, found at http://ess.r-project.org/ [r-project.org] . This lets you interface interactively with R, SAS, Stata, etc., all from the common Emacs interface. As a statistician, it's the one piece of software I could not do very well without!

2) The 'ido' package, with flex matching, in my .emacs,

(require 'ido)
(ido-mode t)
(setq ido-enable-flex-matching t)

This lets you open files and switch buffers with fuzzy matching, really nice when you have lots of things open.

See: http://www.emacsblog.org/2008/05/19/giving-ido-mode-a-second-chance/ [emacsblog.org]

3) Make the mouse jump away when you type over it.
(mouse-avoidance-mode 'cat-and-mouse)

4) Open two windows side-by-side (C-x 3) one with LaTeX code, one with a pdf, then use this in your .emacs, (add-hook 'doc-view-mode-hook 'auto-revert-mode), when you compile the .tex file into PDF, the PDF automatically updates in Emacs, I used that a lot while working on my CV.

5) The thunderbird extension that lets me compose replies in Emacs using emacsclient.

6) org-mode http://www.org-mode.org/ [org-mode.org]

7) preview-latex, now part of AUCTeX, this lets you see preview versions of formulae and graphics inline in your .text file, *while you edit*. Your formula is replaced by what it will look like when compiled.

8) EmacsWiki: http://www.emacswiki.org/ [emacswiki.org]

Meta-/

auto completes based on words that have been seen in the buffer.

Check hard drive

It's often the case when you need to check the sectors on your disk for corruption, or just during hard drive testing. One of the coolest things that Emacs allows you to do is check your filesystem. For example on CentOS:

      yum -y install emacs*

This will proceed to fill up your hard drive with tons of software until the filesystem is full.

(I kid, I kid)

Emacs Lisp

Lisp is a language that CompScis see for two months at University before leaving it behind. But if you really want to learn tricks with Emacs, you should learn Emacs Lisp - I have all sorts of specials, such as "move text to marker" and modes for handling internal IBM dump formats, that would be impossible in vi.

But if you want one quick piece of advice, here's one that should make someone smile

M-x hippie-expand RET

The ultimate, expand-this-thing-dammit-from-whatever-you-like completion trick.

Cheers,
Toby Haynes

Beginning of line

My two .emacs modifications I find essential follow.

First, turning off of obnoxious misfeatures:

(fset 'yes-or-no-p 'y-or-n-p) ; stop forcing me to spell out "yes"
(setq inhibit-startup-message t)
(setq backup-directory-alist '(("." . "~/.emacs-backups"))) ; stop leaving backup~ turds scattered everywhere

And second, stealing the beginning-of-line behavior from Dev Studio: if you invoke the command at the beginning of the line, advance to the first non-whitespace-character instead.

(defun dev-studio-beginning-of-line (arg)
  "Moves to beginning-of-line, or from there to the first non-whitespace character.
 
This takes a numeric prefix argument; when not 1, it behaves exactly like
\(move-beginning-of-line arg) instead."
  (interactive "p")
  (if (and (looking-at "^") (= arg 1)) (skip-chars-forward " \t") (move-beginning-of-line arg)))
(global-set-key "\C-a" 'dev-studio-beginning-of-line)
(global-set-key [home] 'dev-studio-beginning-of-line)

trying to figure something out

I like emacs but I'm not ready to change over to it 100% yet.

Is there a way to dual boot between Vista and emacs?

The old Emacs vs Vi story

I asked my email-pal: "UNIX or Windoze?". He replied "UNIX". I said "Ah...me too!".

I asked my email-pal: "Linux or AIX?". He said "Linux, of course". I said "Me too".

I asked him: "Emacs or vi". He replied "Emacs". I said "Me too. Small world."

I asked him: "GNU Emacs or XEmacs?", and he said "GNU Emacs". I said "oh, me too."

I asked him "GNU Emacs 19 or GNU Emacs 20"? and he said "GNU Emacs 19". I said "oh, me too."

I asked him, "GNU Emacs 19.29 or GNU Emacs 19.34", and he replied "GNU Emacs 19.29". I said "DIE YOU OBSOLETE NOGOOD SOCIALLY MALADJUSTED CELIBATE COMMIE FASCIST DORK!", and never emailed him again.

From an old slashdot [slashdot.org] story

Rectangle Cut and Paste

Working with rectangular regions is a breeze in emacs (very useful for quickly swapping columns in csv-type files):

Set the mark at the upper left of the rectangle... move the cursor the lower right...

Kill rectangle: c-x r k

Move somewhere else...

Yank rectangle: c-x r y

There are some other rectangle commands, but these are probably the two most useful "unknown" emacs commands I've come across.

-Chris

Re:A favourite (works well on both Ubuntu and Debi

There, fixed that for me!

I've found this very useful whenever I'm put in front of emacs
C-x C-c
sudo apt-get -y purge emacs
vi

Re:A favourite (works well on both Ubuntu and Debi

Hmm.. that didn't work well for me. I tried it, but I ended up in an editor with functionality that was one step above punch cards.

Re:A big disappointment

it was posted from emacs, took a while to press all the keys.

Re:Please Stop

Hopefully this is the last story before we start with "Stupid pet tricks"

Seeing as this is about emacs tricks, everything else is a subset. Including pet tricks.

Don't get me wrong: Emacs is a great operating system -- it lacks a good editor, though.

Re:Please Don't Stop

This is the first content I've seen in years that appeals to Slashdot's original demographics: hardcore geeks who are passionate about the tools they use. I've picked up a few tips in this series of articles and have enjoyed hearing other people learn about "old" stuff for the first time.

If "(Stupid) Useful $GEEK Tricks" isn't your cup of tea, then please feel free to look elsewhere [digg.com].

Re:Please Stop

A whole series...
Useful(Stupid) things to say to get modded Insightful
Useful(Stupid) things to say to get modded Interesting
Useful(Stupid) things to say to get modded Funny
Useful(Stupid) things to say to get modded Troll
Useful(Stupid) things to say to get modded Redundant
Useful(Stupid) things to say to get modded Flamebate
Useful(Stupid) things to say to get modded Overrated
Useful(Stupid) things to say to get modded Stupid
Useful(Stupid) things to say to get modded Useful

Re:What is next ?

(Stupid) Useful Chat-up Lines

hey, sexy mama. wanna kill all the humans?