I have to adjust to 4 space indentation for a project I'm collaborating on at work. I hate looking at it, being accustomed to a nice compact 2 space indentation. Is there any way to have emacs display 2 spaces as one? Or maybe tabify on file load, and untabify on save. I'm working in c++. I have searched through google, but can't seem to find an answer to this.
You can try using prettify-symbols-mode, which is built into Emacs >=24.5.
(defun jpk/contract-spaces ()
(add-to-list 'prettify-symbols-alist '(" " . ?\ ))
(prettify-symbols-mode 1))
(add-hook 'c-mode-common-hook 'jpk/c-contract-spaces)
This changes the display, not the content of the buffer or file. I'm not sure this is the best idea. It will affect (auto)indentation and you won't see what the saved file will look like.
Related
I'm updating some fortran 77 code to use fortran 90 constructs and emacs is my editor of choice. Currently, the source is in fixed format and that isn't going to change any time soon (due to external constraints). The two emacs major modes that I can choose from are fortran-mode which only highlights the syntax for fortran 77 constructs (It doesn't understand module or contains, etc. as keywords which I find pretty annoying, but it does understand fixed format -- correctly indenting the code where necessary). The other major mode I could use is f90-mode, however, that gets the indentation all wrong which is also slightly annoying. Is there any way to get the syntax highlighting from f90-mode, but the indentation structure used in fortran-mode?
It looks like this is indeed possible. Try adding the following to your config file:
(require 'f90)
(add-hook 'fortran-mode-hook 'f90-font-lock-2)
This is just following the solution provided on emacs.stackexchange.com, so thanks should flow to user deprecated!
You can achieve some fortran90 like highlighting in fortran-mode by adding
(add-hook 'after-change-major-mode-hook
(lambda () (font-lock-add-keywords 'fortran-mode
'(
("\\(CONTAINS\\)" 1 font-lock-keyword-face t )
("\\(USE\\)" 1 font-lock-keyword-face t )
))))
to your ~/.emacs (or ~/.emacs.d/init.el) file.
For a comprehensive solution some additional work with regular expressions would be needed. But with a few lines, you should be able to feel comfortable with your code. Different colors can be gained by using different faces:
font-lock-comment-face
font-lock-constant-face
font-lock-function-name-face
font-lock-keyword-face
font-lock-type-face
font-lock-warning-face
I'm using auto-complete-mode which I think is totally fantastic. I'm also a big fan of linum-mode but I've got a very irritating issue when the two are used together, especially when I'm working in a new buffer (or a buffer with very few lines).
Basically the buffer is 'x' lines long but when auto-complete kicks in it "adds" lines to the buffer, so linum-mode keeps switching, for example, between displaying line numbers on one column or two columns, depending on whether auto-complete is suggesting a completion or not.
So you type a sentence and you see your buffer's content frantically shifting from left to right at every keypress. It is really annoying.
I take it the solution involves configuring the linum-format variable but I don't know how.
Ideally it would be great if my linum-format was:
dynamic
right-aligned
considering there are 'y' more lines to the buffer than what the buffer actually has
My rationale being that auto-complete shall not suggest more than 'y' suggestion and that, hence, the two shall start playing nicely together.
For example, if 'y' is set to 20 and my buffer has 75 lines, then linum should use two columns: because no matter where I am auto-complete shall not make the buffer 'bigger' than 99 lines.
On the contrary, if 'y' is still set to 20 and my buffer has 95 lines, then linum should use three columns because otherwise if I'm near the end of the buffer and auto-complete kicks in my buffer shall start "wobbling" left and right when I type.
I'd rather not hardcode "3 columns wide" for linum.
I guess using "dynamic but always at least two columns" would somehow fix most annoyances but still something as I described would be great.
P.S: I realize that my 'fix' would imply that linum would always display on at least two columns, and I'm fine with that... As long as it stays right-aligned and use 2, 3 or 4 columns depending on the need.
Simply put the following line in .emacs which resolves this issue. It is in auto-complete.el.
(ac-linum-workaround)
I've written a couple of previous answers on modifying the linum-mode output, which you could probably adapt to your purposes.
Relative Line Numbers In Emacs
Colorize current line number
Edit: Here's the most basic version of that code (also on EmacsWiki, albeit somewhat buried), which doesn't modify the default output at all, but uses the techniques from those other answers to be more efficient than the default code. That's probably a more useful starting point for you.
(defvar my-linum-format-string "%4d")
(add-hook 'linum-before-numbering-hook 'my-linum-get-format-string)
(defun my-linum-get-format-string ()
(let* ((width (length (number-to-string
(count-lines (point-min) (point-max)))))
(format (concat "%" (number-to-string width) "d")))
(setq my-linum-format-string format)))
(setq linum-format 'my-linum-format)
(defun my-linum-format (line-number)
(propertize (format my-linum-format-string line-number) 'face 'linum))
Just have the same problem, after seeing 'patching the source' I believe it could be done with advice. Here is what I come up with
(defadvice linum-update
(around tung/suppress-linum-update-when-popup activate)
(unless (ac-menu-live-p)
ad-do-it))
I would like to use popup-live-p as mentioned but unfortunately it requires the variable for the popup, which we couldn't know in advance.
Update:
I ended up patching the source for linum.el. I added an extra hook that runs before updates.
Here's the patched file: linum.el (github)
Here's the code I have in my init.el:
;; Load custom linum.
(load-file "~/.emacs.d/linum.el")
;; Suppress line number updates while auto-complete window
;; is displayed.
(add-hook 'linum-before-update-hook
'(lambda ()
(when auto-complete-mode
(if (ac-menu-live-p)
(setq linum-suppress-updates t)
(setq linum-suppress-updates nil)))))
Hope it helps!
I'm currently using whitespace-cleanup in my save hook. Using indent-tabs-mode, I'm able to save files without any tabs.
All is well, I don't want tabs in my files. But.
Makefiles do need tabs. That is my problem. How do I change my settings for makefile-mode?
I tried to setq either indent-tabs-mode (the doc says it becomes buffer-local) or whitespace-style, it does not work.
OK, my bad. Files were loaded before changing the mode.
The following code works fine, provided it is loaded in the .emacs before opening any file (I have my own project manager which re-opens last files).
(defun my-tabs-makefile-hook ()
(setq indent-tabs-mode t))
(add-hook 'makefile-mode-hook 'my-tabs-makefile-hook)
I've had the same problem, and it seems that this is a bug in Emacs (as of 24.2). Try this, using the following .emacs:
(setq-default indent-tabs-mode nil)
(add-hook 'after-save-hook 'whitespace-cleanup)
If you open a file, save it, and then open a Makefile, you'll have the problem you described. But if you open a Makefile first, save it, and then open another type of file, you'll have the opposite problem: 8 spaces will be replaced by tabs.
The problem is that indent-tabs-mode is buffer-local, but in whitespace.el it is set to a regular variable called whitespace-indent-tabs-mode. Hence, the first value that's seen is the one that counts.
Here's another workaround that solves some other problems too. Add this to your .emacs:
(defadvice whitespace-cleanup (around whitespace-cleanup-indent-tab
activate)
"Fix whitespace-cleanup indent-tabs-mode bug"
(let ((whitespace-indent-tabs-mode indent-tabs-mode)
(whitespace-tab-width tab-width))
ad-do-it))
The best solution I have found for whitespace is ethan-wspace. It cleans up any whitespace that you made dirty yourself but leaves other whitespace intact.
It works for tabs in makefiles and avoids the messy diff problem where there are lots of diff lines that are just whitespace changes
I am trying to use setnu.el to give me line numbers in emacs, which as you might imagine I want in pretty much every mode. It seemed like the preffered way of doing this in Emacs is to use
(add-hook 'text-mode-hook 'turn-on-setnu-mode)
but this isn't working for me. Using
(add-hook 'emacs-lisp-mode-hook 'turn-on-setnu-mode)
works just fine when I am editing emacs lisp files, but I want line numbers in all my text viewing and don't want to have a special case for each kind of file in my init.d file. Help would be much appreciated.
Linum seems to be distributed with emacs >=22.
Try:
(require 'linum)
Then toggle the display of line numbers with
M-x linum-mode
http://web.student.tuwien.ac.at/~e0225855/linum/linum.html
I've recently moved from vim to Emacs because I want to use org-mode. I opened a ~10000 line, 50kb file in Emacs23 Org-mode and proceeded to add about 10 first-level headings. Performance on a quad-core with 3GB RAM in Emacs23 under Ubuntu 10.04/32bit was so slow that it was unusable. I found two threads on the Org-mode email list discussing this. It seems that enabling linum causes the slow performance. I can live without line numbers in .org files if I have to, but I don't want to disable line numbers for all files I edit. If I'm going to "live" in `Emacs', I'll want line numbers for all other files.
How can I disable linum for some or all .org files only? Is it possible to do this if I have several files open in Emacs and switch between them? I found some discussion about disabling line numbers for major modes here, but there was nothing that I could implement (although the linum-off.el script mentioned on the page looks promising, I don't (yet) know (E)Lisp, so I can't change it as I would need).
I updated Org-mode from version 6.21b which came with Emacs23 to version 7.5, but it made no difference. Performance in Emacs GUI is so bad that the application fails to respond at all. Performance with -nw is "better", but still unusable.
Try adding this to your .emacs:
(defun nolinum ()
(global-linum-mode 0)
)
(add-hook 'org-mode-hook 'nolinum)
This is assuming that you use linum and not something else to number lines. Anyway, you can add this hook to org-mode to disable anything that might make org slow only when you're using org-mode.
Disclaimer: I don't have linum installed so I can't test this, but it should work.
If you type M-x customize, go to Linum in the Convenience group, change Linum Eager to off, or change Linum Delay to on, it will improve performance greatly.
On my laptop (3 GB RAM, dual core) the performance drawback (of this versus having linum off) is unnoticeable, however on my netbook there may still be some slight performance issues with a ~3000 line 130KB file (~50-150 ms delay when paging).
linum-off.el mentioned in my quesiton has solved this. Instructions are in the file: place the file into the Emacs load-path and add (require 'linum-off) to ~/.emacs. This script turns off line numbering for the modes specified only. I've tested it and it works fine.
Use nlinum, a much faster alternative.
You only need to add (add-hook 'org-mode-hook (lambda () (linum-mode 0))).
I tried the following which worked out pretty well:
(defun nolinum ()
(interactive)
(message "Deactivated linum mode")
(global-linum-mode 0)
(linum-mode 0)
)
(global-set-key (kbd "<f6>") 'nolinum)
(add-hook 'org-mode-hook 'nolinum)
Of course, you do not need the keybinding. I suggest you leave it in for testing purposes and disable it if everything works fine.