i am using emacs 23.2 and reference configurations from purcell https://github.com/purcell/emacs.d
i met a problem when i am edit ruby file and rails file, see below
steps:
1. move the cursor to somewhere
2. hit "RET" key to add more new line, then move the cursor to somewhere
3. the red space happened at the last new line.
do you know how to turn this mark off?
What's your problem with this feature? The red space goes away as soon as you
start typing doesn't it?
The feature is show-trailing-whitespace, and it's meant to help you see
spurious space at EOL. Which is very helpful for team development
environment, as checking in such code will annoy your teammates.
What you should do is add a before-save-hook that removes spurious
whitespace see:
http://www.emacswiki.org/emacs/DeletingWhitespace#toc3
code:
(add-hook 'before-save-hook 'delete-trailing-whitespace)
If you want to disable show-trailing-whitespace as well:
(add-hook 'ruby-mode-hook (lambda ()
(setq show-trailing-whitespace nil)))
You might like to look at the ws-trim.el library, which removes trailing whitespace from lines which you edit, but by default does not remove them from other lines*.
I find this best for version-control (compared to deleting all trailing whitespace upon saving), as you do not introduce changes in other people's work if you edit the same file.
(*) although it is also nicely configurable if you want it to do more than that.
Related
Upon save ( I think ), my emacs is deleting trailing white space. I don't want to commit those changes, only the parts I manually modify. Is there a way to disable that behaviour?
This behaviour is not standard. It is however a very common customization that you might have borrowed somewhere. Look for something like the following in you init file and comment out those lines to get rid of this behaviour (and have Emacs save files as they are, without removing whitespace altogether):
(add-to-list 'write-file-functions 'delete-trailing-whitespace)
or
(add-hook 'before-save-hook 'delete-trailing-whitespace)
This emacswiki page gives tons of advice on handling trailing whitespace.
If you want to delete trailing whitespace only on lines you modify, you could try the ws-trim package
Like suggested in this answer the deleting-trailing-whitespace hook might have been added to the before-save-hook hook.
To disable this eval (remove-hook 'before-save-hook 'delete-trailing-whitespace) (type M-:).
Take a look at ethan-wspace. It will clean up any whitespace that you made dirty yourself. However any incorrect whitespace that was there when you opened the file is left intact. This way you can avoid those messy diffs full of whitespace changes
I'm trying to get doremi working in emacs. Specifically, at this stage, to allow me to quickly scroll through a condensed list of color-themes and see each theme as I go through it. For this I would use the 'M-x doremi-color-themes+' command.
What I've done:
Installed color-themes (successfull)
Installed doremi.el, doremi-cmd.el, ring+.el and added
(add-to-list 'loadpath "~/elisp/themes")
(add-to-list 'loadpath "~/elisp/doremi/")
(require 'color-theme)
(color-theme-initialize)
(color-theme-classic)
;; create a list of color themes to scroll through using 'doremi-cmd
(setq my-color-themes (list 'color-theme-classic
'color-theme-retro-green
'color-theme-gray30
'color-theme-subtle-hacker
'color-theme-jonadabian-slate))
(require 'doremi)
(require 'doremi-cmd)
(require 'ring+)
to the .emacs file.
What emacs does:
When I type the comand 'M-x doremi-color-themes+' into the mini-buffer it seems to accept that I've given it a valid command and tells me to use the and arrow keys to move through the list. But when I do that all that happens is the cursor moves up and down in the active window. No changing of color-themes.
Being somewhat new to emacs (and especially customising it) I'm sure I have missed a step or put something in the wrong place. Perhaps there's some sort of (setq 'bla-bla-bla (...)) I need to do?
Sorry for your trouble. Please state your Emacs version (M-x emacs-version), and your version of color-theme.el.
You do not need to require library ring+.el if you use Emacs 23 or later (its code was included in GnuEmacs 23.)
You do not need to use (color-theme-initialize) or (color-theme-classic). The former is done automatically by doremi-color-themes+.
Try starting from emacs -Q (i.e., no init file, ~/.emacs), to be sure there is no interference from stuff in your init file.
Your variable my-color-themes is not referenced anywhere. Instead of defining that variable, just customize user option doremi-color-themes. (Or leave its value nil, which means that all color themes will be cycled through.)
Feel free to contact me by email if you continue to have a problem. Or continue here, if you prefer.
[Just to be sure: you are using color-theme.el, right? There is a lot of confusion out there between Emacs "custom themes" and color themes. Do Re Mi supports both, but they are different critters.]
After a bit for back and forth with #Drew we found a solution to the problem.
It turned out the major problem was that I was using emacs in 'terminal mode' rather than as a GUI application. Bare in mind I'm using a mac.
In the context of Terminal, my arrow keys send escape sequences and so doremi cannot read the event as intended. So it just escapes and applies the message to the active buffer.
There is an answer.
By adding the following lines to my .emacs file (or whatever your init file for emacs is) I was able to redirect doremi to use two other keys. ie. not the up and down arrows.
(setq doremi-down-keys '(?n))
(setq doremi-up-keys '(?p))
Doing this tells doremi to use 'n' as the down key and 'p' as the up key. And all works just fine.
Because I am only new to the world of programming and computing I may often use incorrect terminology. If this is the case please let me know and I will edit accordingly for clarity and consistency.
Upon save ( I think ), my emacs is deleting trailing white space. I don't want to commit those changes, only the parts I manually modify. Is there a way to disable that behaviour?
This behaviour is not standard. It is however a very common customization that you might have borrowed somewhere. Look for something like the following in you init file and comment out those lines to get rid of this behaviour (and have Emacs save files as they are, without removing whitespace altogether):
(add-to-list 'write-file-functions 'delete-trailing-whitespace)
or
(add-hook 'before-save-hook 'delete-trailing-whitespace)
This emacswiki page gives tons of advice on handling trailing whitespace.
If you want to delete trailing whitespace only on lines you modify, you could try the ws-trim package
Like suggested in this answer the deleting-trailing-whitespace hook might have been added to the before-save-hook hook.
To disable this eval (remove-hook 'before-save-hook 'delete-trailing-whitespace) (type M-:).
Take a look at ethan-wspace. It will clean up any whitespace that you made dirty yourself. However any incorrect whitespace that was there when you opened the file is left intact. This way you can avoid those messy diffs full of whitespace changes
Goal: I want to have show-trailing-whitespace enabled for all buffers save a few. Exceptions posing a problem are *Shell Command Output* and its cousin *Async Shell Command*.
I usually have show-trailing-whitespace customized to t. Therefore it is active in all new buffers.
I would also like to have it turned off for certain buffers, foremost amongst them *Shell Command Output*. This poses a problem for me:
The output buffer doesn't use a special mode; it is still in fundamental-mode. There is no fundamental-mode-hook that I could hook this setting into.
There is the after-major-mode-change-hook which is run when the major mode is changed to fundamental-mode, but the buffer starts out in that mode and therefore this hook is not run.
There doesn't seem to be a way to hook into get-buffer-create.
I know I can always advise the function get-buffer-create for this particular example, but I try to avoid that as much as possible.
Any hints?
You might be better off looking at the problem from the other side, and only set the var in those modes where you want to see trailing whitespace.
But I think you have a good point: these shell output buffers should not use fundamental-mode. It's probably time for M-x report-emacs-bug
In accordance with the accepted answer, here's a code snippet that enables trailing whitespaces highlighting for specific modes only:
(setq-default show-trailing-whitespace nil)
(defun namespace/show-trailing-whitespace ()
"Highlight trailing whitespaces in this buffer."
(setq-local show-trailing-whitespace t))
(dolist (hook '(prog-mode-hook text-mode-hook))
(add-hook hook 'namespace/show-trailing-whitespace))
This snippet is essentially taken from Steve Purcell's configuration.
I personally keep all lines under 80 characters, but I also work on projects in teams where other programmers don't care about line length.
I love using whitespace-mode, but the long line visualization is really annoying when I'm working on projects where I shouldn't interfere with the long lines. It seems like it should be easy to turn off the long line visualization---I hit m-x global-whitespace-toggle-options l, and then can hit m-x global-whitespace-toggel-options ? to confirm that the "long-line visualization" is turned off. But long lines are still highlighted. I kill buffers and reload them, and highlighting is still there. I'm definitely using global, not local, whitespace-mode.
Why can't I turn off the long line visualization?
The last time I customized whitespace-mode, I noticed that my changes to the settings didn't have any effect in buffers that already existed; try recreating the buffer, or leaving and reentering whitespace-mode. In case you don't already know, you can use M-x customize-group whitespace to turn off that particular option entirely, rather than doing it manually.
Edit: Specifically you want to customize the whitespace-style variable. This lets you turn on and off individual styles. In this case you should turn off the ones labelled "(Face) Lines" and "(Face) Lines, only overlong part". The former changes the face of the whole line when it is overly long, while the latter only changes the face of the part that extends past the threshold.
(Other options in this group define the faces that whitespace-mode will use to highlight the styles you've turned on, the regexes it uses to identify certain situations, etc, but usually you only care about whitespace-style).
Set whitespace-line-column to a higher value (default is 80), so the highlighting of long lines doesn't kick in:
(setq whitespace-line-column 250)
I'm assuming that you already have whitespace-mode activated somewhere in your init.el or similar. If so, you can adapt duma's comment above, and either
Edit the elisp that sets whitespace-style to remove lines-tail. E.g., Emacs Prelude sets
(setq whitespace-style '(face tabs empty trailing lines-tail))
Simply change that to
(setq whitespace-style '(face tabs empty trailing))
If you don't want to directly edit that elisp, but rather override it later with your own code, do something like
(setq whitespace-style (delete 'lines-tail whitespace-style))
Unfortunately, if running Prelude with auto-loaded buffers (using something like Emacs Desktop), the initial setting will take precedence: for each buffer on which you want to see whitespace-style displayed as directed, you must [1]
kill the buffer
re-open the buffer
[1]: Note to OP: if there's another way to reload a buffer, please edit or comment this answer. I was hoping to find something like M-x reload-buffer but am not seeing anything like that with C-h a buffer.