When I type r in Emacs dirmode, it goes into a mode that allows directory operations (such as renaming, moving, deleting) by editing the list.
I have a certain file, say, foo, and I want to create a new directory below its original directory, name that directory as foo, and move the file into that directory, and give it a different name, say bar:
/path/to/the/file/foo
↓
/path/to/the/file/foo/bar
I edited the list in this mode, and did save, but the operation failed. It looks like editing like this does not allow creating directories. Is there some hack that I can do to let this possible?
I have lots of similar tasks to do, and editing on the emacs dirmode is easiest for me to do than writing a shell script to do it.
You can override your implementation of wdired-do-renames as follows (the idea being just to create each destination file's parent directory before doing the rename):
diff --git a/lisp/wdired.el b/lisp/wdired.el
index 2e53944..cc838cf 100644
--- a/lisp/wdired.el
+++ b/lisp/wdired.el
## -490,6 +490,7 ## non-nil means return old filename."
(require 'dired-aux)
(condition-case err
(let ((dired-backup-overwrite nil))
+ (wdired-create-parentdirs file-new)
(dired-rename-file file-ori file-new
overwrite))
(error
## -499,6 +500,10 ## non-nil means return old filename."
err)))))))))
errors))
+(defun wdired-create-parentdirs (file-new)
+ "Create parent directories of destination filename."
+ (message "create dir for file %s" file-new)
+ (make-directory (file-name-directory file-new) t))
(defun wdired-exit ()
"Exit wdired and return to dired mode.
Source: Joakim Verona via http://www.emacswiki.org/emacs/WDired#toc1 (I cleaned up the patch just a bit)
AFAIK, you cannot create a directory that way, i.e., when in wdired mode (which is what you are in when the Dired buffer is editable).
However, you can just exit wdired (C-x C-q) and then use + to create a directory.
(BTW, I think you have a typo: C-r in Dired does not toggle wdired mode, i.e., editability/read-only. It just invokes isearch-backward. You use C-x C-q to toggle read-only.)
Related
This is a very simple request: I want to create a new, blank file without giving it a name (yet). I can use the scratch buffer but there's only one. I can C-x C-f and open a new file, but then I have to give it a name and path. If I'm just writing notes to myself or sketching out ideas, I don't want to have to give it a name. How do I create a new, empty, unnamed file?
You can create a new buffer with: C-xb and type in the buffer name and it will create a new buffer with a name that you choose.
If you want to save that buffer, just hit C-x w to create the file with its contents to a desired location.
My recommendation is that you give org-mode a try. It will do what want among a million other things.
Give it a name. Just don't save it.
Not what you wanted to hear, but this is the Emacs way.
Use C-x C-f, giving the (to-be-file-visiting) buffer a name. Edit the text. Do not use C-x C-s to save the buffer to the file (i.e., to disk).
Note that you can first put yourself in a directory whose contents you don't care about, so that if you accidentally do save the buffer there then you can easily find, recognize and toss the file. To change directories, you can use M-x cd. Or just do it by editing the directory part when you first use C-x C-f. Or use C-x d to put yourself in a Dired buffer for the directory.
If you don't want to take the chance of accidentally hitting C-x C-s and thus saving your edits, then use C-x b instead of C-x C-f. You are (even here) prompted for the buffer name. Giving it a new name (not the name of an existing buffer) creates a new buffer. In this case, if you use C-x C-s then Emacs prompts you for the file location to save the buffer in.
Why would you want to use C-x C-f instead of C-x b, if you might not want to save the buffer? Providing a file extension in the file name you give automatically puts the buffer in the proper major mode (typically). Otherwise (for C-x b) you need to put the buffer in the mode you want.
Buffer *scratch* is by default in Lisp-Interaction mode, which is similar to Emacs-Lisp mode (but not the same).
In every other text editor or word processor the intuition is to create a “new file” or a “new buffer”, not to switch to idiosyncratic *scratch* buffer. For example, you write quick notes or thoughts in several different buffers to keep trace of them—later you decide if you throw them away or save them. Or you manipulate a snippet of text or code, but you don't want to change the original buffer, so you just copypaste it to a new temporary buffer.
*scratch* is set to Lisp Interaction mode, but if I want to quickly evaluate some Elisp code, I could eval it running eval-expression (Alt+:) or in Elisp interpreter IELM (Alt+x Enter ielm). Also, if you close *scratch* buffer, it doesn't ask you to save it, so you can accidentally lose all your work. Drew's traditional solution seems too sub-optimal. And I don't buy the argument that “this is how you do it in Emacs”. Emacs is a customizable editor, so you can and should create whatever workflow is comfortable for you.
That's how ErgoEmacs solves it, buy creating a new-empty-buffer command. You can implemented like this:
(defun new-empty-buffer ()
"Opens a new empty buffer."
(interactive)
(switch-to-buffer (generate-new-buffer "untitled"))
(funcall initial-major-mode)
(put 'buffer-offer-save 'permanent-local t)
(setq buffer-offer-save t))
The variable buffer-offer-save resets every time you change a major mode, therefore you need to annotate it with permanent-local. It also prompts only when you exit Emacs. I think it is intuitive for it to also ask, when you close a modified untitled buffer, therefore see my solution on how to upgrade kill-buffer to prompt before closing a modified buffer.
ErgoEmacs revamps the default keybindings completely and has new-empty-buffer bound to Ctrl+N, like in almost all software. Change variable initial-major-mode if you want the new buffer to have another mode on start.
See also:
Emacs: Problems of the Scratch Buffer # Xah Lee
Emacs: New Empty Buffer # Xah Lee
You can try the following snippet, just add it to your .emacs
(defun new-file-tmp()
"Create a new empty file."
(interactive)
(let ((buf (generate-new-buffer "untitled")))
(switch-to-buffer buf)
(put 'buffer-offer-save 'permanent-local t)
(setq buffer-offer-save t)))
(defun tool-bar-local-item-pre (icon def key map after_item &rest props)
"Add an item to the tool bar in map MAP.
ICON names the image, DEF is the key definition and KEY is a symbol
for the fake function key in the menu keymap. Remaining arguments
PROPS are additional items to add to the menu item specification. See
Info node ‘(elisp)Tool Bar’. The item is added after AFTER_ITEM.
ICON is the base name of a file containing the image to use. The
function will first try to use low-color/ICON.xpm if ‘display-color-cells’
is less or equal to 256, then ICON.xpm, then ICON.pbm, and finally
ICON.xbm, using ‘find-image’."
(let* ((image-exp (tool-bar--image-expression icon)))
(define-key-after map (vector key)
`(menu-item ,(symbol-name key) ,def :image ,image-exp ,#props) after_item)
(force-mode-line-update)))
(when (boundp 'tool-bar-map)
(tool-bar-local-item-pre "new" 'new-file-tmp 'new-file-tmp tool-bar-map
'new-file :label "" :help "New untitled File")
(define-key tool-bar-map (vector 'new-file) nil)
;; comment the above line if you want to keep the button for the default behavior
)
(global-set-key (kbd "C-n") 'new-file-tmp)
It defines a new command which creates new empty buffers
Then the code binds it to the top left button of the toolbar, if you are in gui mode, and to the Control-n shortcut.
You can check the post on my site about it.
disclaimer: it's my site
A buffer and a file are not the same thing.
terminology
Regarding buffers,
The text you are editing in Emacs resides in an object called a
buffer. Each time you visit a file, a buffer is used to hold the file's text.
Regarding files,
The operating system stores data permanently in named files, so most
of the text you edit with Emacs comes from a file and is ultimately
stored in a file.
Buffers and files are related through visiting,
Visiting a file means reading its contents into an Emacs buffer so you
can edit them. Emacs makes a new buffer for each file that you visit.
answering the question
Unless I'm mistaken, technically speaking, your question, as written, can't be answered. Pedantically speaking, there's no such thing as (or little practical use for) an unnamed file. A file is a handle for something stored on disk. If you have no handle, then why make a file?
The question can then be interpreted as having two possible meanings1.
1. Making a new buffer (without regard to name)
A new buffer must have a name. An unsaved buffer can be saved to file with a given name using write-file (C-x C-w). You will be prompted for a path/name. Once written, the buffer update to be visiting the file you just wrote.
Since the name of the buffer doesn't matter (until you write it to file), here's a function which creates buffers named *scratch1*, *scratch2*, ... .
(defun create-scratch-buffer ()
"Create a new numbered scratch buffer.
Taken from URL `https://stackoverflow.com/a/21058075/5065796' "
(interactive)
(let ((n 0)
bufname)
(while (progn
(setq bufname (concat "*scratch"
(if (= n 0) "" (int-to-string n))
"*"))
(setq n (1+ n))
(get-buffer bufname)))
(switch-to-buffer (get-buffer-create bufname))
(org-mode)
(if (= n 1) initial-major-mode)))
2. Making a new file (without regard to name)
As hinted at in the new buffer solution, new files can be created with write-file.
When called interactively (M-x make-random-file), this function prompts for a directory. It then writes an empty file named something random like tmp-17388716387615.txt.
(defun make-random-file (dir)
"Make a random file in DIR."
(interactive "DDir: ")
(let* ((filename (concat "tmp-" (int-to-string (random t)) ".txt"))
(filepath (concat dir filename)))
(write-region "" nil filepath nil 'silent nil 'excl)))
As always, if the code above doesn't make sense, look at the documentation for functions and variables with C-h f and C-h v, respectively. And/or read the Introduction to Programming in Emacs Lisp.
1 It was the second meaning which I was searching for solutions to when I found this as the top search engine hit. Apologies if this was a bit obtuse. Figured it was better to share my solutions with y'all than not. :)
I wrote a new note in Emacs howm-mode. Now I want to delete it, and I am not able to do so. Should I delete the associated file on my system? Any help is appreciated!
Use Emacs "directory editor", dired, though I think of it simply as a directory explorer.
Use C-x d to bring up a mini-buffer prompt for where to open dired.
I use ido-mode and a vertical presentation to make that mini-buffer easier to use, with these settings,
(ido-mode 1)
(setq ido-decorations '("\n-> " "" "\n " "\n ..." "[" "]"
" [No match]" " [Matched]"
" [Not readable]"
" [Too big]" " [Confirm]"))
(setq ido-default-buffer-method 'selected-window)
In dired, if you type ?, it will show
d-elete, u-ndelete, x-punge, f-ind, o-ther window, R-ename, C-opy, h-elp
in the mini-buffer, so for instance, to delete the file under cursor, type d x.
Useful commands include + to create a new directory, or using m to mark several files, then R to move them all to a new directory, or ^ to jump to the containing directory. (I rarely use ^, it's too far away from home row's j. More often I use dired-x's more general C-x C-j, described below, or selecting the .. you see in dired's buffer.) To create a file, simply use the global C-x C-f binding. More exotic commands would as usual be found in the menu-bar or manuals.
I would recommend the following settings to make dired easier to look at, in a minimal way,
(setq dired-details-hidden-string "")
(require 'dired-x)
(setq-default dired-omit-files-p t)
(setq dired-omit-files "^\\.$")
(when (locate-library "dired-details")
(require 'dired-details)
(dired-details-install))
You can use ( and ) to hide and reveal file information (dired-details), and M-o to toggle hiding of hidden files (dired-x).
dired-x also provides a dired-jump function, bound to C-x C-j, which will jump to the directory containing the current window's file.
The when (locate-library... statement is to prevent errors if you haven't installed dired-details, as it is not built-in to Emacs.
Actually, deleting the associated file from my system did delete the note.
Good enough.
I just wonder if there was a way to do it from within emacs/howm...
I work on an open source project where the creator sets his tab-indents to 2 spaces.
I'd like to just enable it on the fly for the one file I work on and not other files of the same type. There must be something like M-x set-tab-indent. It is a JavaScript file ending in .js.
I know I can use:
(setq-default tab-width int)
inside my .emacs file, but I rather just call an M-x command to set it and forget it during my duration of working on this file. I tried M-x apropos and Google but couldn't find the specific command.
Thanks.
You can make the variable js-indent-level local to the buffer using:
M-x make-variable-buffer-local <RET> js-indent-level <RET>
Then you can set that variable in the buffer using:
M-x set-variable <RET> js-indent-level <RET> 2
The easiest way to do this for a single buffer is to use M-x set-variable.
Type M-x set-variable and press enter
When prompted for the variable to set, set tab-width then press enter
You'll be prompted with the line Set tab-width (buffer-local) to value:.
Put the value you want, then hit enter
The buffer should instantly be updated with the new value.
You could also use file local variables to automate omrib's solution for that one file, by adding this to it:
// Local Variables:
// js-indent-level: 2
// indent-tabs-mode: nil
// End:
Create a file ".dir-locals.el" in the project's directory and fill it like this:
((nil . ((tab-width . 2))))
This will take care of setting tab-width automatically and you don't have to modify the actual file (which is likely version-controlled.)
See the manual for more information about the format. I believe this requires Emacs 23.
As indicated by others, one issue with the File Local Variables approach is that you need to modify the file, and that's not ideal if you need to keep those declarations out of version control.
If you want the variables to apply to all files under a given directory, then Directory Local Variables is obviously the way to go, and you can implement that with either a .dir-locals.el file, or by calling (dir-locals-set-directory-class):
http://www.emacswiki.org/emacs/DirectoryVariables
http://www.gnu.org/software/emacs/manual/html_node/emacs/Directory-Variables.html
I prefer the directory class approach myself, and I was thinking that it's a shame that there isn't an analogous approach for file local variables, but I found that the directory class code actually works perfectly with files, and the only issue is that dir-locals-set-directory-class calls file-name-as-directory on its argument, which prevents it from being matched, due to the trailing slash.
The following therefore is a way to configure directory local variables for a single file, without modifying the file itself, or affecting other files under the same parent directory.
(defun my-file-locals-set-directory-class (file class &optional mtime)
"Enable 'directory local' classes for individual files,
by allowing non-directories in `dir-locals-directory-cache'.
Adapted from `dir-locals-set-directory-class'."
(setq file (expand-file-name file))
(unless (assq class dir-locals-class-alist)
(error "No such class `%s'" (symbol-name class)))
(push (list file class mtime) dir-locals-directory-cache))
(dir-locals-set-class-variables
'my-javascript-class
'((nil . ((js-indent-level . 2)
(indent-tabs-mode . nil)))))
(my-file-locals-set-directory-class
"path/to/the/file.js" 'my-javascript-class)
I use a snippet of code in my init.el that tries to auto-detect files that use 2-space indents, and switch Emacs's indentation for that file to 2 spaces when it sees such files:
(add-hook 'js-mode-hook
(lambda ()
(when (string-match-p "^ [A-Za-z]" (buffer-string))
(make-variable-buffer-local 'js-indent-level)
(set-variable 'js-indent-level 2))))
When I start working on a project in emacs, I use M-x cd to get into the project root directory. But every time I use C-x C-f to open a file in one of the subdirectories (like app/model/Store.rb) emacs changes current directory to that of the file. Is there a way to make emacs stay at the root?
How about this? It replaces the regular find-file command with your own which always starts in some "root" directory (customize the find-file-root-dir variable):
(defvar find-file-root-dir "~/"
"Directory from which to start all find-file's")
(defun find-file-in-root ()
"Make find-file always start at some root directory."
(interactive)
(let ((default-directory find-file-root-dir))
(call-interactively 'find-file)))
(global-set-key (kbd "C-x C-f") 'find-file-in-root)
Assuming that you want the working directory of a file to be set to whatever the working directory was before you executed find-file, you could try the following:
(defmacro disallow-cd-in-function (fun)
"Prevent FUN (or any function that FUN calls) from changing directory."
`(defadvice ,fun (around dissallow-cd activate)
(let ((old-dir default-directory) ; Save old directory
(new-buf ad-do-it)) ; Capture new buffer
;; If FUN returns a buffer, operate in that buffer in addition
;; to current one.
(when (bufferp new-buf)
(set-buffer new-buf)
(setq default-directory old-dir))
;; Set default-directory in the current buffer
(setq default-directory old-dir))))
Armed with this macro, go search for operations that set the variable default-directory: M-x find-library files; M-x occur (setq default-directory. After some investigation, you discover that the desired function is called find-file-noselect-1. Also, it looks like set-visited-file-name is also a candidate. So:
(disallow-cd-in-function find-file-noselect-1)
(disallow-cd-in-function set-visited-file-name)
Note
Note that (disallow-cd-in-function find-file) would work just fine, but then if you switched to ido-mode, you'd be opening files with ido-find-file instead of find-file. Both of these functions ultimately use find-file-noselect-1, so hitting that with the macro is a more univeral solution.
Is there a way to make emacs stay at the root?
No, there isn't. C-x C-f always visits starting from the default directory of the buffer you are already vising. The default directory, by default, is the same directory as the file. You can change these (separately for every buffer) using M-x cd.
But that is not what you want. What you should do is C-x b to *scratch* (whose default directory is the same as where you launched Emacs from -- in your words "root"), and then visit a new file. And if you need to do this frequently, just open up a dired in there and work your way thru.
I appreciate I'm not answering your question directly, but I noticed you were more specific in your requirements in one of your comments: "I don't use compile or recompile, I just tend to close files I am not working on, since it takes fewer keystrokes to open a file again".
Have you got ido turned on for buffer switching? If you exclude the directory thing for a moment, switching files or buffers with ido is an identical number of keystrokes (C-x C-f vs C-x b, followed by a few characters in the file name). If you include the directory thing, switching files is more tricky for the precisely the reasons you mention. Sticking with buffers is much easier.
Going a step further, with the help of 'anything.el' it's quite easy to abstract away whether a given file is in a buffer or in a file using the file cache. For example, if you do the following:
(file-cache-add-directory-recursively "/my/ruby/project") ".*\\.rb$")
and run 'anything-for-files' (I have it bound to C-x f) all your open buffers are listed, along with all of the files you've just added to the file cache; isolating a given file usually only takes one or two more characters.
Any file in your project is thus 4 or 5 key presses away, and the directory they are in or whether or not they are in a buffer becomes irrelevant.
Hope that's helpful...
Sorry I haven't worked out the details, but you might be able to add a function to find-file-hook that resets the default directory to whatever you want.
One problem that I have with emacs is that it doesn't seem to handle like-named files in different directories very well. For example, if I'm not careful, I'll end up with 20 __init__.py buffers open. What I've been doing is using M-x rename-buffer and renaming it to indicate what package it's within. However, doing this manually is somewhat tedious.
Does anyone have any strategies for attacking this problem?
I like uniquify, which comes with Emacs:
(require 'uniquify)
(setq uniquify-buffer-name-style 'reverse)
(setq uniquify-separator "/")
(setq uniquify-after-kill-buffer-p t) ; rename after killing uniquified
(setq uniquify-ignore-buffers-re "^\\*") ; don't muck with special buffers (or Gnus mail buffers)
With those settings, the directory gets added to the buffer name, giving you an indication of where the file is. For example, loading the files /some/path/to/Makefile and /some/path/to/different/Makefile would result in the following buffer names:
Makefile/to (which is /some/path/to/Makefile)
and
Makefile/different (which is /some/path/to/different/Makefile)
uniquify also handles updating the buffer names when buffers are deleted, so when one of the two Makefile buffers is deleted, the other gets renamed to simply Makefile.
If you want full control you can redefine create-file-buffer.
If you want the full filename it could be as simple as
(defun create-file-buffer (filename)
"Create a suitably named buffer for visiting FILENAME, and return it."
(generate-new-buffer filename))
See files.el for reference.