I recently added the line
(set-default-font "-misc-fixed-medium-r-semicondensed--13-120-75-75-c-60-iso8859-1")
to my .emacs file. After that find-file-other-window always opens a new window instead of utilizing existing windows. Why would that happen!? How can I fix it?
I don't understand how all this font-config magic works, so if it's actually obvious I'm sorry.
Edit: I have a pretty large resolution, and my font size has decreased pretty significantly. Does find-file-other-window take into account available character space? Perhaps it's deciding there's sooo much room it can afford to just open windows willy nilly.
find-file-other-window ultimately calls display-buffer, which runs a complex algorithm to decide whether to reuse an existing window or make one and how. In particular, if display-buffer decides it needs to create or recycle a window, it tries calling split-window-preferred-function to split the biggest window. By default, split-window-preferred-function is split-window-sensibly, which is willing to split windows vertically if they are more than split-height-threshold lines high, or failing that horizontally if they are more than split-width-threshold columns wide.
It looks like you want
(setq split-width-threshold nil)
(setq split-height-threshold nil)
N.B. This answer applies to GNU Emacs 23. Earlier versions didn't have horizontal splitting. Later versions may do things differently.
A few ways to find this out (none straightforward):
If you guess that what's going on is called splitting a window: M-x apropos RET split RET shows a number of variables and functions, and you might figure out which ones are relevant. Or if you guess that there's an option (there often is), C-h v split- TAB shows promising leads.
The documentation for find-file-other-window references Displaying Buffers. (You have to go to the Elisp manual for this level of detail; within Emacs, C-h i m elisp RET brings up the Elisp manual, and i find-file-other-window RET leads you to the documentation for this function.) It's less clear that pop-to-buffer is the passage to read there; it references Choosing Window which contains the sought after information.
C-h f find-file-other-window RET shows the built-in documentation for the function. It links to display-buffer. The description of display-buffer doesn't describe its operation in detail, so from there you need to either consult the Elisp manual as above or explore the source of display-buffer by clicking on window.el.
Related
In Emacs I'm editing some source code, and I hit <tab>. Emacs indents the line to n spaces. I'd like to change the amount that indents for that kind of line. How do I figure out what rule emacs applied to indent that line by n spaces?
I want to change n, but I need to figure out which of the many indentation-related variables Emacs just used.
A generic answer is difficult. Some modes will make this more apparent than others, but in the general case (as they are free to implement indentation however they wish) I don't think you'll get away from needing to read some elisp.
Starting with the binding for TAB will work, but might be slightly time-consuming depending on how many layers of indirection are involved.
If you know that the major mode in question implements its own indentation, then one (non-rigorous, but fast) approach that you could try to help track down the functions being called is to use ELP, the built in elisp profiler. elp-instrument-package will instrument for profiling all functions with names matching the prefix string argument you specify. Therefore you might do something like the following in a PHP file (noting that php-mode tells you that it is derived from c-mode)
M-x elp-instrument-package RET php- RET
M-x elp-instrument-package RET c- RET
M-x elp-instrument-package RET indent RET
Now type TAB in your source code, and run M-x elp-results to see which of those instrumented functions were called.
At this point you're on your own -- look for the likely suspects, and see what the code is doing -- but it can be a handy way to filter the search.
Once you've finished, use M-x elp-restore-all to prevent any further profiling.
If you're using a mode based on cc-mode (e.g. c-mode, c++-mode, java-mode, etc.), you can hit C-c C-s and it'll tell you what syntactic category the line is. If you want to change it, hit C-c C-o and you'll be guided through the process. Check out the cc-mode docs on customization for more details: https://www.gnu.org/s/emacs/manual/html_node/ccmode/Customizing-Indentation.html
If you happen to enjoy getting your hands really dirty, there's always the elisp debugger to tell you just what Emacs is up to.
If you hit C-h k TAB you'll find the function that Emacs is running (e.g. indent-for-tab-command) then you can do M-x debug-on-entry RET indent-for-tab-command RET. Now whenever you hit TAB you'll pop up a debugger and can watch the execution step by step.
Depending on your taste for debugging, it's either a maddening or enlightening experience. Either way, don't forget to M-x cancel-debug-on-entry when you're done.
I've recently started using emacs and I'm enjoying using it for the most part. The only thing I'm not enjoying, is switching between buffers. I often have a few buffers open and I've grown tired of using C-x b and C-x C-b, are there any packages that make switching between buffers easier? I've looked into emacs wiki on switching buffers and I'd appreciate insight/feedback on what are are using/enjoying. Thanks.
UPDATE: iswitchb-mode is obsolete in Emacs >= 24.4, replaced by ido.
All of the features of iswitchdb are now provided by ido. Ross provided a link to the documentation in his answer. You can activate with the following in your .emacs (or use the customization interface as Ross suggests):
(require 'ido)
(ido-mode 'buffers) ;; only use this line to turn off ido for file names!
(setq ido-ignore-buffers '("^ " "*Completions*" "*Shell Command Output*"
"*Messages*" "Async Shell Command"))
By default, ido provides completions for buffer names and file names. If you only want to replace the features of iswitchb, the second line turns off this feature for file names. ido will ignore any buffers that match the regexps listed in ido-ignore-buffers.
The behaviour described below for iswitchb-mode applies equally to ido for switching buffers.
iswitchb-mode (Emacs < 24.4)
iswitchb-mode replaces the default C-x b behaviour with a very intuitive buffer-switching-with-completion system. There are more sophisticated options, but I've never needed more than this.
After you hit C-x b, you are presented with a list of all buffers. Start typing the name of the buffer you want (or part of its name), and the list is narrowed until only one buffer matches. You don't need to complete the name, though, as soon as the buffer you want is highlighted hitting enter will move you to it. You can also use C-s and C-r to move through the list in order.
You can turn it on by default with this in your .emacs:
(iswitchb-mode 1)
You can also tell it to ignore certain buffers that you never (or very rarely) need to switch to:
(setq iswitchb-buffer-ignore '("^ " "*Completions*" "*Shell Command Output*"
"*Messages*" "Async Shell Command"))
You can use C-x <right> (next-buffer) and C-x <left> (previous-buffer) to cycle around in the buffer ring. You could bind S-<right> and S-<left> to these functions. (S is the "super-key" or windows-key). This way you can save some keystrokes.
Moreover, note that C-x b has a default entry, i.e. it displays a standard value (most of the time this is the previously viewed buffer), so that you don't always need to enter the buffer name explicitly.
Another nice trick is to open separate windows using C-x 2 and C-x 3. This displays several buffers simultaneously. Then you can bind C-<tab> to other-window and get something similar to tabbed browsing.
M-x customize-group ido then set Ido Mode to Turn on both buffer and file and set Ido Everywhere to on. Then click the Save for future sessions button at the top and enjoy ido magic for both files and buffers. Read the docs to get a sense of how to use ido.
Also, take a look at smex.
ido-mode provides an efficient way to switch buffers.
ibuffer is best for managing all opened buffers.
anything is good for selecting an interested thing from different
sources. (for eg: a single key can be used to switch to another
buffer or to open recently closed file or to open a file residing
in the same directory or ... anything you want ... )
If you've looked at the Emacs Wiki, you probably have all this information already, but here are a few other relevant Q&As:
Emacs: help me understand file/buffer management
Buffer switching in Emacs
How to invoke the buffer list in Emacs
My toolkit consists of ibuffer, windmove+framemove, winner-mode, and a custom binding to make C-xleft/right and C-cleft/right less of a hassle to use.
I have mapped the "ยง"-key to 'buffer-list and I find it to be very efficient.
I've started using anything for a couple of days and I'm really liking it: http://www.emacswiki.org/emacs/Anything .
Emacs-fu has an good intro to anything: http://emacs-fu.blogspot.com/2011/09/finding-just-about-anything.html
My favourite function for this is helm-mini which is part of helm.
As other helm functions, it allows incremental narrowing of the selection. It also searches your recently visited buffers, which is a really nice way to re-open a buffer. Helm can be a little surprising at first and as a new Emacs user, I found it visually overwhelming and I preferred ido or ibuffer which have been suggested in other replies. But now I absolutely love it and use it all the time for countless things.
Something that I realized by accident and that can be useful:
mouse-buffer-menu is by default bound to <C-mouse-1> (Control key + mouse left click) and opens a popup with a list of the current buffers.
I have an extensive emacs configuration. Unfortunately, auto-fill-mode is broken within LaTeX-mode for some reason. How can I debug this without binary searching my emacs configuration for the error?
Alternatively, how can I make this function not set an undo point? It's annoying to have to press undo once per word and space in the document.
(local-set-key (kbd "SPC")
(lambda () (interactive) (fill-paragraph)
(insert " ")))
Well, you can try M-x debug-on-entry auto-fill-mode.
But my advice would be to use do the binary search you're trying avoid. There is nothing faster. My init setup is probably at least as extensive as yours, and I sometimes think there is a quicker way to guess what the problem is, and time and again I've been taught the lesson that binary search is the way to go. It just seems slow and silly at first.
Remember the parable of the wise man who convinced a ruler to pay him with one grain rice on the first chessboard square, 2 on the second square, 4 on the third, and so on. It really doesn't get any better than binary search when you have no idea where the problem is, and even often when you think you can guess the general location of the problem. Just do it.
Vim completes words and lines with CTRL-X P and CTRL-L. There's a Emacs plugin called Company mode but this plugin interfere and cause conflicts with lots of things within Emacs (with global linum and yasnippets). I know that I can complete words with CTRL-/ in Emacs. But it is possible to take previously written lines to complete code?
Maybe you're looking for hippie-expand? From that web page (as of this writing, anyway):
HippieExpand looks at the word before
point and tries to expand it in
various ways including expanding from
a fixed list (like expand-abbrev),
expanding from matching text found in
a buffer (like dabbrev-expand) or
expanding in ways defined by your own
functions. Which of these it tries and
in what order is controlled by a
configurable list of functions.
For a comprehensive list of completion options visit the emacs wiki page on completion.
There are a gazillion ways to do completion in Emacs. Some are mode specific, some inline, some configurable and what not. Here is a list of modes that might help you.
Use numberic argument to complete by line, say M-5 M-/ will complete by line, while M-/ alone still complete the normal way.
hippe-expend function has a very useful feature which is :
With a positive numeric argument, jumps directly to the ARG next function in this list. With a negative argument or just C-u, undoes the expansion.
Customize the expansion functions in hippie-expand-try-functions-list and put the function try-expand-line as 5th list element, then you could use M-5 M-/ to complete by line.
This tip is very handy and useful and I highly recommend it.
Also worth noting: if your window manager does not steal Alt-tab, emacs will auto-complete with Alt-tab (I set up my window manager to user the "windows key" instead of alt for this very reason).
If you are using evil, this is the most vim-like solution I use:
(defun my-expand-lines ()
(interactive)
(let ((hippie-expand-try-functions-list
'(try-expand-line-all-buffers)))
(call-interactively 'hippie-expand)))
(define-key evil-insert-state-map (kbd "C-x C-l") 'my-expand-lines)
This way you can use our old friend C-x C-l in insert mode for whole line all buffers completion.
Thanks #ymln for the suggestion of using try-expand-line-all-buffers.
I've recently started using ido-mode, which, overall, is pretty nice. But one thing seems especially broken, and I'm wondering if there's a setting (ha) buried in there to fix it.
ido-switch-buffer doesn't seem to care about buried buffers. That is, if I use bury-buffer, and then ido-switch-buffer, the first choice is often the one I just buried.
Is there an easy way around this? The whole point of burying a buffer is that I don't want to see it again any time soon.
Acording to the documentation (C-h f bury-buffer)
Put BUFFER-OR-NAME at the end of the list of all buffers.
There it is the least likely candidate for 'other-buffer' to return;
thus, the least likely buffer for C-x b to select by
default.
So, if you use bury-buffer the buffer will be still available (at the end of the list), so it's normal that ido-switch-buffer find it.
If you don't want to see that buffer ever, you should think of closing it.
I can't reproduce this. On Emacs 23, as far as I can tell, ido-switch-buffer lists the buffers in the correct order.
In any case, you might try out iswitchb instead. It's kind of like ido, only older and more specific to buffer switching. If you like it, you can use iswitchb for buffer switching and ido for everything else.
can't reproduce this either: when i bury a buffer and call ido-switch-buffer afterwards, the buried buffer is NOT at the front of the switch list.
i have done quite a bit of ido customization (to get it working well with dired, etc), but my main ido settings are:
(setq ido-show-dot-for-dired t)
(setq ido-default-file-method 'samewindow)
(setq ido-default-buffer-method 'samewindow)
(setq ido-confirm-unique-completion t)
(setq ido-max-dir-file-cache 20)
my ido.el version is "1.57 released on gnu.emacs.sources adapted for emacs 22.1".
hth.
Use next-buffer or previous-buffer
FWIW, the default completion behavior of switch-to-buffer (C-x b) in Emacs-24 has been changed to use substring-match completion, so its behavior is similar to IDO while obeying the principle that "the default buffer shouldn't be the one I just buried". You can make it even more similar by turning on icomplete-mode (which does not change the completion behavior itself, but displays the completion candidates at the end of the minibuffer).