Have basic autoindentation in code blocks in org-mode - emacs

Emacs' fine org-mode has CODE and EXAMPLE blocks that are easily edited in a proper major mode using C-c '. But for quick alterations and minor edits one might prefer editing the block inline without opening new popup windows for a two-second operations.
Of course org lets you do that but the automatic indentations are off radar while editing inline like that. Where and what should I hack to make org's indentation logic to act like default dumb autoindentation (ie. copy the indent level of the previous line) while the cursor is in a code block?
#+BEGIN_SRC python
def foo():
return 42
#+END_SRC
#+BEGIN_EXAMPLE
Oh my
hh
#+END_EXAMPLE
If the cursor was at the end of the line containing hh, pressing C-j would get me a new line with the same indentation as the previous one.

The following allows me to edit (and indent) code "inline" without ever going to the indirect buffers (except for M-q on comments, which did work and does not anymore).
;; same effect for `tab' as in the language major mode buffer
(setq org-src-tab-acts-natively t)

Related

Is there a way to disable indentation for one specific org-mode src block at a time?

I'm using most of the standard features of org-mode that come with the spacemacs develop branch, but I haven't been able to find a way to disable the automatic indentation for source code blocks on a case by case basis. I use tangle and I'm writing Dockerfile's in the same file that I'm writing groovy code or javascript for example. The Dockerfile's are the only ones I want not to be indented so I can get syntax highlighting. Here's what it looks like without the indentation:
And here's what it looks like with the indentation that automatically happens if I edit the text:
The automatic indentation is fine for groovy for example, so I have no issue with the automatic indentation here. (in fact, if I still got the syntax highlighting for Dockerfile's I probably wouldn't mind too much except the weird word wrapping not respecting the background face). Here's the example with groovy:
As you can see, I tried a :noindent property I found in the org-mode docs that's usually in a #+STARTUP directive. I also searched stack overflow, but I didn't find anything fruitful that didn't disable indenting for all source blocks or for the entire file.
In my practice (I'm not sure it is a good practice or not, just share it to you):
I setup org-src-tab-acts-natively to true for using the language’s major-mode indentation. In your case, it will format the src block with the formatting rules of dockerfile-mode.
I created a new major-mode plain-mode for the content which should not be indented automatically. Personally, I use this mode for something like:
shell outputs
ASCII diagrams
...
#+begin_src plain
this will not
be
auto
indented
#+end_src
Above src block will not be indented when you select them as region, and TAB on them.
In this way, the src blocks will always behavior as expected when formatting them.
Aside, the example code of plain-mode:
(define-derived-mode plain-mode
clean-mode "Plain"
"Major mode for plain text."
;; preserve the auto indentation on line
(setq-local indent-line-function 'indent-relative)
;; disable auto indentation on region
(setq-local indent-region-function (lambda (start end))))

Emacs - How to wrap selection in org-mode source code block?

I have a bunch of elisp and other code with some notes i wanted to reformat to be more organized, and i found that having to type
#+BEGIN_SRC emacs-lisp ... #+END_SRC
all the time around what i want, is taking a bit longer than expected...
So what i wanted to do instead is to wrap/or put the selected content (with C-space) and put it in a template source code block for org-mode (in my case it's mostly elisp code, but i plan to use it for other things maybe)
How could i do this in emacs or in elisp?
There is a new templating mechanism in recent Org mode (>= 9.0 IIRC) that allows you tor wrap a region in a block: after selecting the region in the usual manner, you say C-c C-, s. You still have to type the emacs-lisp part though. That's the disadvantage. The advantage is that it is general enough to allow you to wrap a region in any kind of block. In your case, I think the disadvantage outweighs the advantage, so I would go with the wrap-region method in the other answer, but this one is good to know as well.
You can try wrap-region. It will allow you to define what type of string you want to wrap around a selection.
Put this in your init.el and evaluate it.
(wrap-region-global-mode t)
(wrap-region-add-wrapper "#+BEGIN_SRC emacs-lisp\n" "#+END_SRC" "#" 'org-mode)
Then, while you are editing your org files, you can select a block of text and type #, which will wrap it with your string. You can change the # to another character that will do the wrapping.
There is a feature in org-mode to do exactly that. It's like a snippet of some sort where you enter <eland hit TAB, the < char is here to say we're gonna use a template and the el part tells which template to use. But of course, you have to configure it first.
For that, you can just add this to an org-mode file or to your init.el file :
#+begin_src emacs-lisp
;; This is needed as of Org 9.2
(require 'org-tempo)
(add-to-list `org-structure-template-alist `("sh" . "src shell"))
(add-to-list `org-structure-template-alist `("el" . "src emacs-lisp"))
(add-to-list `org-structure-template-alist `("py" . "src python"))
#+end_src
There a bunch of way to use this, it's actually more useful than just use it as a template, you can go check the documentation here.

Font-locking for SQL-MODE inside of ORG-MODE not font-locking

Related to question: org-mode: fontify code blocks natively
I've got the latest org-mode and emacs versions as of November 1, 2012 (org stored in org-20121105).
I've also got the sql-mode that comes with emacs-24.
I've got fontification turned one:
;; fontify code in code blocks
(setq org-src-fontify-natively t)
Yet this does not fontify in my org documents. Java, bash, etc. all work.
#+BEGIN_SRC SQL
SELECT foo FROM bar
#+END_SRC
When I open a file foobar.sql, the mode indicator says SQL[ANSI] (which I also tried as the source type), and font-locking works.
Thanks in advance for any tips.
Firstly, the name of the SRC block mode is case-sensitive. It should be sql instead of SQL.
#+BEGIN_SRC sql
SELECT foo FROM bar
#+END_SRC
Secondly, the initial font-lock of sql-mode seams not to highlight SQL keywords, (at least to me, it looks no difference no matter you turn it on or off). Therefore, you need to specify which kind of SQL you want to highlight. If you are using MySQL for example:
(add-hook 'sql-mode-hook
(lambda ()
(sql-highlight-mysql-keywords)))
Then Restart Emacs. It should work now.
Oh, wait, try putting #+BEGIN_SRC sql in lower case. See here for identifiers.
Try refreshing the display, by making the block be reparsed (break the syntax and undo, or something). It often happens to me with python or bibtex blocks, but this fixes it.
I can't see why it wouldn't fontify inline if it finds the right mode when you C-c '.
Also, I'm afraid fontification, while being one of org-mode's nicer features, is not exactly perfectly handled. From the mailing list :
The fontification engine is not very powerful and get easily fooled.

Using Emacs, how could I indent/format a code segment in a TXT file?

I am writing a document with Emacs. As you know, there are some code segments in the text file I am working with. Typically, when I open this file, emacs will get into text-mode automatically. And it works fine for me to edit the ordinary paragraphs. But for those code segments, how could I indent them into gnu or linux style just like what I could do in c-mode (by c-set-style && do Ctrl-Alt-\ in certain region)?
BTW, actually, I could turn the buffer into c-mode by invoking M-x c-mode to do this, however, I think there should be much a graceful way to do this in text-mode.
orgmode manages to do it by copying the code out to a temporary buffer where you edit & format it, and updating the changed text when you're done.
If switching to orgmode is an option, then you do it like this:
#+BEGIN_SRC emacs-lisp
(defun org-xor (a b)
"Exclusive or."
(if a (not b) b))
#+END_SRC
and start and finish editing with C-c '.
Edit: Emacswiki has a list of multiple modes.
You might be able to mark the region, then narrow the view to the region, change the mode, indent, return to text-mode, and return to the full buffer again. I forget the exact shortcuts at the moment, but it should be fairly easy to turn into a function.

How to highlight all occurrences of a word in an Emacs buffer?

Notepad++ has a convenient feature: if you select a word in your text (not necessarily a keyword), the word is highlighted throughout the text. Can this be done in Emacs as well? And if so, how?
It doesn't necessarily have to work exactly like Notepad++ (i.e., via selection); ideally, I would like to set up a key binding that causes all occurrences of the word under cursor to be highlighted.
It would be great if the highlights were permanent, i.e., moving point away from a highlighted word should not cause the highlight to be removed.
Also, it would be useful if there was a solution that made it possible to navigate between highlights (using custom key bindings).
The hi-lock suggestions are good. I think it's easier to use the M-x versions, though:
M-x highlight-regexp RET <REGEXP>
M-x highlight-phrase RET <REGEXP>
highlight-phrase is just a bit of sugar around highlight-regexp that ignores case and translates a space in the regex to match arbitrary whitespace. Handy.
Maybe highlight-symbol.el at http://nschum.de/src/emacs/highlight-symbol/ is what you are looking for:
Type C-s, then type the current word or type C-w. As a bonus, you can now hit C-s again to search for the word.
This is called incremental search.
What I use is idle-highlight
http://www.emacswiki.org/emacs/IdleHighlight
M-x idle-highlight sets an idle timer that highlights all occurences in the buffer of the word under the point.
To enable it for all programming modes, in ~/.emacs.d/init.el:
;; highlight words
(add-hook 'prog-mode-hook (lambda () (idle-highlight-mode t)))
Light-symbol will highlight whatever symbol point is over.
Alternately, you can use occur, which lists all lines matching a regexp. It's useful to quickly see all functions in a class.
Nobody mentioned symbol-overlay mode. It's basically a better rewrite of highlight-symbol-mode. "Better" as in, lacks bugs of original highlight-symbol (such as, temporary highlight getting stuck, or the temporary highlight disappearing for moving inside the highlighted word; or not being able to highlight symbols like *), better integrated, and maintained. See "Advantages" paragraph of its README.
You can install it as usual, with M-xpackage-install (make sure to update package list beforehand with package-list-packages). For reference, at the bottom I attached code I use to enable the mode and disable a few of the more advanced features which you may or may not want.
Notepad++ has a convenient feature: if you select a word in your text (not necessarily a keyword), the word is highlighted throughout the text. Can this be done in Emacs as well? And if so, how?
Once you enable overlay-symbol, occurrences on the screen will be shown for every word that you put cursor upon after a timeout (timeout by default is 0.5s, can be configured with symbol-overlay-idle-time variable). If a word don't get highlighted, this means there's just one match on the screen (the one you put cursor upon), hence there's no need to highlight it.
It would be great if the highlights were permanent, i.e., moving point away from a highlighted word should not cause the highlight to be removed.
To highlight the word under cursor permanently there's a function symbol-overlay-put. To unhighlight call it once again.
In my config example it's bound to Logo+` key.
(require 'symbol-overlay)
(defun enable-symbol-overlay-mode ()
(unless (or (minibufferp)
(derived-mode-p 'magit-mode)
(derived-mode-p 'xref--xref-buffer-mode))
(symbol-overlay-mode t)))
(define-global-minor-mode global-symbol-overlay-mode ;; name of the new global mode
symbol-overlay-mode ;; name of the minor mode
enable-symbol-overlay-mode)
(global-symbol-overlay-mode) ;; enable it
(global-set-key (kbd "s-`") 'symbol-overlay-put)
(setq symbol-overlay-ignore-functions nil) ;; don't ignore keywords in various languages
(setq symbol-overlay-map (make-sparse-keymap)) ;; disable special cmds on overlays
This may not be as nice as what you were hoping but if you put
(global-hi-lock-mode 1)
in your .emacs file then you can type C-x w h REGEX <RET> <RET> to highlight all occurances of REGEX, and C-x w r REGEX <RET> to unhighlight them again. Again, not as elegant as you'd probably like, but it'll work.
Try http://www.emacswiki.org/emacs/msearch.el
All occurences of the text selected with the cursor are highlighted.
You have to drag over the string which you want to highlight. That enables you to easily change the selection without changing the highlight.
If you want to preserve the highlighting of a string you can freeze it.
You can enslave a buffer to another buffer. Text selected in the master buffer will also be highlighted in the slave buffer. That is useful for comparing buffers.
It is also useful for taking notes in one buffer while you investigate the text in another one. You can have a collection of keywords in the notes buffer. Drag over such a keyword and its occurences in the investigated text will be highlighted.
I am using this stuff for years now. I added the freezing quite recently. So, maybe something is broken. If this is the case leave me a note on http://www.emacswiki.org/emacs/msearch or here.
Check Interactive Highlighting
Should be:
C-x w h word <RET> <RET>
Try iedit. It highlights the word at point and lets you edit all occurrences of it easily. With an additional keystroke (C-'), it hides all the lines without that word in it. Very handy!
Commands in library highlight.el
let you (un)highlight text matching a regexp (in this case a symbol), using overlays or text properties. You can cycle among the occurrences. Highlighting can be temporary or persistent. (more info).
This maybe won't highlight but will search for a word without you needing to type it...
when you've reached the word you wanted to search, C-S, then read the full word with C-W then you can C-S and it will search for it. In my Emacs it also highlights all instances in the document.
This package available in Melpa works, you can customize the highlight style as well.
https://github.com/ignacy/idle-highlight-in-visible-buffers-mode