emacs M-e doesn't work properly in tex-mode - emacs

I'm using emacs and auctex to write LaTeX documents. For some reason, M-e doesn't move to the end of the sentence in tex-mode as it did when I went through the tutorial. It moves to the end of the paragraph. (That is, it moves to just before the next double line break)
What is wrong? Do I need to turn on/off some mode to skip to the next full stop? How do I check which modes are active?

I noticed that the same happens in my Emacs. The problem is that the variable sentence-end-double-space is set to t. This means that Emacs expects a sentence to end with a double space. By setting to nil things work properly, i.e., Emacs recognizes a period followed by a single space as the end of sentences.

The first thing to check is what M-e is bound to. In tex-mode, for me, it is bound to forward-sentence. You find this out by C-h k M-e.
It sounds as though it's bound to forward-paragraph, in which case I'd check your .emacs file to see if you've got any overrides in tex-mode hooks, or other things. You can also try running without your .emacs: emacs -q, and seeing what M-e is bound to (to determine if it truly is your .emacs). You can also start without the site lisp file emacs -q --no-site-file - in case your administrators have added anything.

Related

Can I change emacs settings while it's running?

I'm very new to the Emacs text editor and have just started customizing my ~/.emacs file. I'm wondering if it's possible to change an Emacs setting while it's running. For example, if I put the following in my ~/.emacs file:
(show-paren-mode 1)
I can do the same thing when Emacs is running by typing:
M-x then scroll-step then 1.
Why doesn't this work when I want to do something like this:
(setq scroll-step 1)
When I type:
M-x then setq,
all I get is (no match). There must something I'm not understanding here.
There is a few things:
yes, you can change settings at run-time. If you edit your .emacs file, put your cursor after the closing parenthesis in:
(show-paren-mode 1)
And hit ctrl-x ctrl-e and it will evaluate the code.
some things and variables (though very few) require them to run special things after the setting was changed. Generally there aren't too many and most variables you set will take effect immediately after doing the steps in #1.
However, if you edit your settings using M-x customize you'll find that when you make changes there it'll make the settings active immediately, even in those special cases where something special needs to be done after a value change.
M-x allows you to run "interactive" commands. Some elisp functions are supposed to be called directly by the end user, and others are really only meant when writing elisp into a file. And M-x only lets you easily do the ones that have been marked "interactive". Though M-shift-: will let you type an expression and see the results. EG, try M-shift-: followed by (1+ 2) at the prompt.

How to work out which package is unsetting keybindings?

Something in my config is unsetting/overwriting some standard keybindings for C-c C-e so that commands in various major modes don't work properly. In AUCTeX C-c C-e should start the "insert environment" dialogue and in org-mode the same keys should start the export/publish dialogue, but in both of these modes C-c C-e is undefined and emacs just waits for more input.
I know I could start emacs with -Q and load packages until something breaks (and if I load emacs that way and open a file in org-mode, the keybindings work as they should) but, like lots of people, at some point my init file became monstrously big. Is there a quicker, smarter way?
[EDIT] Nothing in my config is unsetting C-c C-e explicitly.
The debugger might give you enough clues to sort it out. Try adding the following to the beginning of your .emacs:
(debug-on-entry 'global-unset-key)
You might need to try 'local-unset-key as well. For details see the debugger manual.
Binary search is your friend.
Go to the middle of your .emacs and add (error "here"), then launch Emacs and see if the problem persists.
If it does, then insert another error line half way between the current and the top of the file, if not, comment out the current error and add one half way between the current and the bottom.
Repeat the bisection process until you isolate the line or two which are responsible for causing the problem.
You could use C-h k C-c C-e to find out which function is bound to your combination.
In the popped up help buffer, you will get the function name, its documentation and a link to the file where it is defined. Follow that link and you will end up at the place of the function definition.
At this point, it should be simple to identify which package that is responsible for redefinition of your keybinding using the name of the file.
If this does not help, you could M-x rgrep in your customization directory for 'C-c C-e' or 'C-e' and manually check everything.

Turn off Emacs Whitespace-mode "Long Line" Visualization

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.

Remove Emacs highlighting

I use the emacs command 'highlight-compare-buffers' to see the changes between two files. But I don't know how to turn the highlighting off. It seems like it should be really easy, but I can't seem to figure out how even with lots of googling and searching the emacs help files.
Try:
C-u -1 M-x highlight-compare-buffers
global-highlight-changes is an
interactive autoloaded Lisp function
in `hilit-chg'.
(global-highlight-changes &optional
arg)
Turn on or off global Highlight
Changes mode.
When called interactively:
if no prefix, toggle global Highlight Changes mode on or off
if called with a positive prefix (or just C-u) turn it on in active mode
if called with a zero prefix turn it on in passive mode
if called with a negative prefix turn it off
I don't have emacs installed on this box, so this is untested, but highlight-changes-toggle-visibility might work.

how do I disable Flyspell?

It sounds easy but I can't fix it: I want to permanently disable automatic spell-checking in emacs. There must be a simple line for my init.el. Can somebody help me?
Figure out why it's on in the first place (it isn't enabled by default), then fix that. Either your init file is turning it on, or else some system-wide init file is. Read about those files: http://www.gnu.org/software/emacs/manual/html_node/emacs/Init-File.html
From a brief look, the simplest way I can see is to redefine the function:
(eval-after-load "flyspell"
'(defun flyspell-mode (&optional arg)))
or you could use advice to force the argument to always be -1 (see C-h f turn-off-flyspell), but that would be slightly more complex and less efficient for no good reason.
If you want to know what is running it in the first place, you could use M-x debug-on-entry flyspell-mode, which will show a stack trace when the function is called (q to exit the debugger; C-h m to list other commands; M-: (info "(elisp)debugger") for help). Use M-x cancel-debug-on-entry to remove that breakpoint.
(flyspell-mode 0)
I found mine in ~/.emacs.d/usk/text.el
I deleted the block of code having to do with FlySpell and closed emacs.
After reopening emacs, I still saw the spelling error (red underline). However, I simply deleted and retyped the "misspelled" words and then, emacs didn't underline. Problem solved.
I'm running Debian.
In my case flyspell-mode has been gaining ground in the .emacs.desktop file.
This was not the first time that desktop-mode causes pain in restoring obsolete things. In this case it restored all modes on a per-file basis, although in .emacs.el I had already disabled flyspell-mode and flyspell-prog-mode everywhere.
Solution: either edit the .emacs.desktop file or delete it.
Using Emacs graphical mode you can just right click above "Fly" minor mode bellow and select "Turn Off minor mode" like this: