I have the following file data.txt
A
B
C
D
I would like to read the contents of this file into a Lisp list, like
(defun read-list-from-file (fn)
(interactive)
(list "A" "B" "C" "D"))
(defun my-read ()
(interactive)
(let (( mylist (read-list-from-file "data.txt")))
(print mylist t)))
How can I modify read-list-from-file such that it returns the same list, but instead reads from the file given as input argument fn.. Each line in the file should be a separate item in the list..
This code:
(with-current-buffer
(find-file-noselect "~/data.txt")
(split-string
(save-restriction
(widen)
(buffer-substring-no-properties
(point-min)
(point-max)))
"\n" t))
UPD:
Here's a version with insert-file-contents:
(defun slurp (f)
(with-temp-buffer
(insert-file-contents f)
(buffer-substring-no-properties
(point-min)
(point-max))))
(split-string
(slurp "~/data.txt") "\n" t)
Much easier, than creating a temporary buffer, is to use f file manipulation library's f-read function that returns textual content of a file (default coding UTF-8).
f is a third-party that you need to install from MELPA, read Xah Lee's tutorial on how to use Emacs package management system. Then you could use either split-string or s string manipulation library's s-split (which is a simple wrapper around the former function):
(s-split "\n" (f-read "~/data.txt") t) ; ("A" "B" "C" "D")
Note: third parameter to s-split set to t omits empty strings. You could use s-lines, but as textual files on *nix systems usually contain a trailing newline, the returned list would be ("A" "B" "C" "D" ""). You can remove the last element with dash list manipulation library's butlast function, but this works in O(n), so probably stick to s-split, unless you want empty lines to be preserved in the list.
Related
I have a list of org files under a directory:
> org-file1.org
> org-file2.org
> org-file3.org
> ...
> org-fileN.org
I want to extract their titles (using #+title tag) as links as follows:
[[file:org-file1.org][title for org file 1]]
[[file:org-file2.org][title for org file 2]]
[[file:org-file3.org][title for org file 3]]
...
[[file:org-fileN.org][title for org file N]]
How can I extract these as a list using Emacs Lisp?
You could use the org-element-api for this, but in this case it is probably easier/faster to simply search by regexp using looking-at-p. To get all files in a directory, there is directory-files(-recursively). Then finally you could achieve it using the following function:
(defun extract-org-directory-titles-as-list (&optional dir)
(interactive "D")
(print
(delete nil
(let ((case-fold-search t))
(mapcar (lambda (f)
(when (string-match "org$" f)
(with-temp-buffer
(insert-file-contents-literally
(concat (file-name-as-directory dir) f))
(while (and (not (looking-at-p "#\\+TITLE:"))
(not (eobp)))
(forward-line))
(when (not (eobp))
(cons f (substring (thing-at-point 'line) 9 -1))))))
(directory-files dir))))))
(defun insert-directory-org-file-titles (&optional dir)
(interactive "D")
(let ((files-titles (extract-org-directory-titles-as-list dir)))
(dolist (ft files-titles)
(insert (concat "[[file:" (car ft)"][" (cdr ft) "]]\n")))))
If you prefer to just have it as a (a)list, like you asked, then just use extract-org-directory-titles-as-list.
Here's some code that can be used on a single file to get the title. It's part of an org mode file that can be used for testing. Save it as an Org mode file, visit it in Emacs and type C-c C-c on the code block. Change the title and evaluate the code block again.
#+OPTIONS: toc:nil
#+TITLE: This is a very nice title, don't you think?
#+AUTHOR: A.U. Thor
* foo
bar
* Code
#+begin_src elisp :results drawer
(save-excursion
(goto-char (point-min))
(let ((case-fold-search t))
(search-forward-regexp "^#\\+TITLE:")
(org-element-property :value (org-element-context (org-element-at-point)))))
#+end_src
#+RESULTS:
:results:
This is a very nice title, don't you think?
:end:
The code block goes to the beginning of the buffer, searches forward for the string #+TITLE: at the beginning of a line (the search is case-insensitive) and then uses some functions from the org-element library to parse the buffer at point, get the context and get the :value property out of it.
In order to make it into a complete solution, you have to:
make it more robust: check that this is a title keyword not just some random junk that happened to satisfy the match, although that's unlikely; but better safe than sorry.
wrap it in a loop that does a find-file on every file in the directory and gets the title for each file and returns a list of tuples: (filename title) that you can easily use to create your links.
Sometimes I want to create a duplicate of a number of files (say, config files), which initially should have the same content as the initial files. Therefore I'd like to be able mark some files in dired and "duplicate" them, this duplication procedure could work similar like the duplication procedure utilised by most file managers, when pasting to the original directory: The file names of the duplicated get "(Copy)" appended (just before the file extension).
I can't seem to find a built-in dired function that does this, maybe someone can help/has already created a function like this?
Help is much appreciated!
There is one function that does what you want: dired-do-copy-regexp
Example of use:
mark the files
M-x dired-do-copy-regexp
\(.*\)\.\(.*\)
\1 (copy).\2
For a file named foo.txt you will be creating another named foo (copy).txt
Note that my first regexp has two groups, and the second regexp references them. You can do much more complicated things, if needed.
Maybe you will want to rename the functions (I didn't come up with better names), maybe some more elaborate formatting, if you wish...
(defcustom dired-keep-marker-version ?V
"Controls marking of versioned files.
If t, versioned files are marked if and as the corresponding original files were.
If a character, copied files are unconditionally marked with that character."
:type '(choice (const :tag "Keep" t)
(character :tag "Mark"))
:group 'dired-mark)
(defun dired-version-file (from to ok-flag)
(dired-handle-overwrite to)
(dired-copy-file-recursive from to ok-flag dired-copy-preserve-time t
dired-recursive-copies))
(defun dired-do-version (&optional arg)
"Search for numeric pattern in file name and create a version of that file
with that number incremented by one, or, in case such file already exists,
will search for a file with the similar name, incrementing the counter each
time by one.
Additionally, if called with prefix argument, will prompt for number format.
The formatting is the same as is used with `format' function."
(interactive "P")
(let ((fn-list (dired-get-marked-files nil nil)))
(dired-create-files
(function dired-version-file) "Version" fn-list
(function
(lambda (from)
(let (new-name (i 0) (fmt (if arg (read-string "Version format: " "%d") "%d")))
(while (or (null new-name) (file-exists-p new-name))
(setq new-name
(if (string-match "^\\([^0-9]*\\)\\([0-9]+\\)\\(.*\\)$" from)
(concat (match-string 1 from)
(format fmt
(+ (string-to-number (match-string 2 from)) (1+ i)))
(match-string 3 from))
(concat from (format (concat "." fmt) i)))
i (1+ i))) new-name)))
dired-keep-marker-version)))
(define-key dired-mode-map (kbd "c") 'dired-do-version)
Also, I've originally used v to bind this function because I don't use dired-view, but you would need to bind that inside direds hook. c just was the first undefined key, so I used it.
In the Dired mode, put cursor on the file you want to duplicate or mark that file, then press "C". You will be prompted for new name.
You can use this feature to copy files between Dired buffers as well. To make it possible put into your init file:
(setq dired-dwim-target t)
I'm trying to convert a website into an ebook, and there is a huge chunk of html at the beginning of every page which I want to delete. As you can imagine, using Q results in no matches due to something in the big chunk not being escaped properly. When I try and regex the problem away, I get stack overflow.
What I really need is a way to find and replace in dired without regex, in the usual M-% way. Is this possible?
The regexp behaviour is optional in theory, but the function calls in question hard-code that assumption in a few places. I think the simplest solution is to make copies which don't set the regexp flags when they run.
(eval-after-load 'dired
'(define-key dired-mode-map (kbd "C-c Q") 'my-dired-do-query-replace))
(defun my-dired-do-query-replace (from to &optional delimited)
"Do `query-replace' of FROM with TO, on all marked files.
Third arg DELIMITED (prefix arg) means replace only word-delimited matches.
If you exit (\\[keyboard-quit], RET or q), you can resume the query replace
with the command \\[tags-loop-continue]."
(interactive
(let ((common
(query-replace-read-args
"Query replace in marked files" nil t)))
(list (nth 0 common) (nth 1 common) (nth 2 common))))
(require 'dired-aux)
(dolist (file (dired-get-marked-files nil nil 'dired-nondirectory-p))
(let ((buffer (get-file-buffer file)))
(if (and buffer (with-current-buffer buffer
buffer-read-only))
(error "File `%s' is visited read-only" file))))
(my-tags-query-replace
from to delimited '(dired-get-marked-files nil nil 'dired-nondirectory-p)))
(defun my-tags-query-replace (from to &optional delimited file-list-form)
"Do `query-replace' of FROM with TO on all files listed in tags table.
Third arg DELIMITED (prefix arg) means replace only word-delimited matches.
If you exit (\\[keyboard-quit], RET or q), you can resume the query replace
with the command \\[tags-loop-continue].
Fourth arg FILE-LIST-FORM non-nil means initialize the replacement loop.
Fifth and sixth arguments START and END are accepted, for compatibility
with `query-replace', and ignored.
If FILE-LIST-FORM is non-nil, it is a form to evaluate to
produce the list of files to search.
See also the documentation of the variable `tags-file-name'."
(interactive (query-replace-read-args "Tags query replace" nil t))
(require 'etags)
(setq tags-loop-scan `(let ,(unless (equal from (downcase from))
'((case-fold-search nil)))
(if (search-forward ',from nil t)
;; When we find a match, move back
;; to the beginning of it so perform-replace
;; will see it.
(goto-char (match-beginning 0))))
tags-loop-operate `(perform-replace ',from ',to t nil ',delimited
nil multi-query-replace-map))
(tags-loop-continue (or file-list-form t)))
I've got some json that I'd like to process in emacs. I've found and used the elisp library to extract the desired content from the json, and I'd like to replace the json with the elisp equiivalent that I've extracted.
This is what I've written:
(defun extract-foo (start end)
"Extract the foo field from a json object in the region"
(interactive "r")
(let ((my_json (cdr (assoc 'FOO (json-read-from-string (buffer-substring-no-properties start end))))))
(delete-region start end)
(SOMETHING)
))
I'm stuck at the something. I can't seem to find a way to write the contents of my_json to the buffer at the mark. The only way I can think of is to save the text instead to a temporary buffer, and then (insert-buffer) it. This seems excessive to me though.
How can I do this idiomatically in elisp?
to write back JSON partial
(insert (format "%s" (json-encode my-json)))
to write back elisp:
(insert (format "%s" my-json))
Note that your use of underscore in variable naming is contrary to convention.
I'm looking for some help developing what I think should be an easy program.
I want something similar to Emacs tags-search command, but I want to collect all search results into a buffer. (I want to see all results of M-,)
I'm thinking this python style pseudo code should work, but I have no idea how to do this in emacs lisp? Any help would be greatly appreciated.
def myTagsGrep(searchValue):
for aFile in the tag list:
result = grep aFile seachValue
if len(result) > 0:
print aFile # to the buffer
print result # to the buffer
I would like to be able to browse through the buffer with the same features tags-apropos does.
Note that a similar question has been asked before:
Is there a way to get emacs tag-search command to output all results to a buffer?
Since I'm such a fan of igrep, I'd use it as the building block. From there it's two simple routines and you're done. With that library and these two functions, all you have to do is:
M-x igrep-tags ^SomeRegexp.*Here RET
Here's the code:
(require 'igrep)
(defun igrep-tags (regex)
(interactive "sTAGS Regexp: ")
(igrep igrep-program regex (tags-file-names)))
(defun tags-file-names ()
(save-excursion
(visit-tags-table-buffer)
(mapcar (lambda (f) (file-truename f))
(tags-table-files))))
And, because the list of files can get really long, and you likely don't care what that list is, you can add these two pieces of code which will make the filenames invisible after the grep has finished:
(add-hook 'compilation-finish-functions 'igrep-tags-hide-filenames)
(defun igrep-tags-hide-filenames (buffer stat)
"hide the filenames b/c they can get long"
(save-excursion
(set-buffer buffer)
(save-match-data
(goto-char (point-min))
(if (search-forward (combine-and-quote-strings (tags-file-names))
nil
(save-excursion (forward-line 10) (point)))
(let ((display-string "..<files from TAGS>.."))
(put-text-property (match-beginning 0) (match-end 0) 'invisible t)
(put-text-property (match-beginning 0) (match-end 0) 'display display-string))))))
To avoid the really long command line, you can use the following code (which creates a temporary file containing all the names of files from TAGS file and uses that instead):
(defun igrep-tags (regex)
(interactive "sTAGS Regexp: ")
(let ((igrep-find t)
(igrep-use-file-as-containing-files t))
(igrep igrep-program regex nil)))
(defvar igrep-use-file-as-containing-files nil)
(defadvice igrep-format-find-command (around igrep-format-find-command-use-filename-instead activate)
"use the second argument as a file containing filenames"
(if igrep-use-file-as-containing-files
(progn (with-temp-file
(setq igrep-use-file-as-containing-files (make-temp-file "tags-files"))
(insert (combine-and-quote-strings (tags-file-names))))
(setq ad-return-value (format "cat %s | xargs -e %s"
igrep-use-file-as-containing-files
(ad-get-arg 0))))
ad-do-it))
And, for those using Emacs 22 or earlier, you'll need the routine that's shipped with Emacs 23 (from subr.el)
(defun combine-and-quote-strings (strings &optional separator)
"Concatenate the STRINGS, adding the SEPARATOR (default \" \").
This tries to quote the strings to avoid ambiguity such that
(split-string-and-unquote (combine-and-quote-strings strs)) == strs
Only some SEPARATORs will work properly."
(let* ((sep (or separator " "))
(re (concat "[\\\"]" "\\|" (regexp-quote sep))))
(mapconcat
(lambda (str)
(if (string-match re str)
(concat "\"" (replace-regexp-in-string "[\\\"]" "\\\\\\&" str) "\"")
str))
strings sep)))
Here is the code I use to create a tag system for my personal notes. It uses bookmarks and treats each word in a bookmark as a single tag. Its not quite what you're looking for but it might get you started.
The first couple of functions are probably already implemented in emacs, but I wrote my own for reasons that I no longer recall.
;; FILTER keeps only elements of li for which pred returns true
(defun filter (pred li)
(let (acc)
(dolist (elem li)
(if (funcall pred elem)
(setq acc (cons elem acc))))
(reverse acc)))
(defun string-match-all-p (str li)
(if li
(if (string-match-p (car li) str)
(string-match-all-p str (cdr li))
nil)
t))
;;bookmarks as tags
(defun lookup-bookmark-tags (tagstring)
(interactive "s")
(let ((taglist (split-string tagstring " ")))
(let ((bookmark-alist (filter
(lambda (elem)
(string-match-all-p (car elem) taglist))
bookmark-alist)))
(call-interactively 'list-bookmarks))))
I then bind the 'tagging' behavior to a key (F11) and the 'lookup' behavior to another (F12).
(global-set-key [f11] 'bookmark-set)
(global-set-key [f12] 'lookup-bookmark-tags))
Hope that is useful to you.
This is what you want:
http://www.emacswiki.org/emacs/Icicles_-_Emacs_Tags_Enhancements#icicle-tags-search
This is the doc string for icicle-tags-search:
Search all source files listed in tags tables for matches for REGEXP.
You are prompted for the REGEXP to match. Enter REGEXP with `RET'.
You do not need `M-,' - you see all matches as search hits to visit.
All tags in a tags file are used, including duplicate tags from the
same or different source files.
By default, all tags files are used, but if you provide a prefix
argument then only the current tag table is used.
If your TAGS file references source files that no longer exist, those
files are listed. In that case, you might want to update your TAGS
file.
You can alternatively choose to search, not the search contexts as
defined by the context regexp you provide, but the non-contexts, that
is, the text in the files that does not match the regexp. To do this,
use `C-M-~' during completion. (This is a toggle, and it affects only
future search commands, not the current one.)
See also this page for more explanation about Icicles search:
http://www.emacswiki.org/emacs/Icicles_-_Search_Commands%2c_Overview