I've got a function to insert the current date into my file
(defun insert-date ()
(interactive)
(insert
(format-time-string "%m-%d-%Y")))
This works for inserting the date into my current buffer, however the output is 01-24-2011nil
How can I remove the nil from the input.
As noted above, insert returns nil and inserts the arguments as a side effect. Since you've declared your function interactive, you can call it using M-x. Even if you don't declare it interactive, you can say M-: (insert-date).
It's the C-j that is inserting nil. The function itself as you've defined it is OK. C-j in the scratch buffer is useful for debugging Lisp that you have written, but you have to remember that it will insert the return value. If you don't want that, try C-x C-e instead.
Related
I'm trying to call the following org-mode function to insert the current timestamp in the buffer. The function is called by a script.
(org-time-stamp-inactive)
This, as expected, brings up a prompt asking for the date to use for the timestamp. But I want to skip the prompt and insert the timestamp directly. Is that possible at all? Haven't found anything that could help me.
This should insert the current inactive time stamp:
(org-insert-time-stamp nil nil t)
org-time-stamp unconditionally¹ calls org-read-date to prompt the user for a date. You can't pass a date. But you can locally bind org-read-date to a function that returns the date that you want to use.
(require 'cl)
(flet ((org-read-date (org-with-time &rest args)
(format-time-string (if org-with-time "%Y-%m-%d %H:%M" "%Y-%m-%d")
(current-time))))
(org-time-stamp-inactive with-time))
¹ Except sometimes when there is already a time stamp, but that's no help.
I ended up creating the timestamp from scratch with the following call:
(insert (format-time-string "[%Y-%m-%d %a]"))
You can find the answer in documentation for similar function (org-time-stamp)
[...] With two universal prefix arguments, insert an active timestamp
with the current time without prompting the user. [...]
So.. all you need to do is press C-u C-u before you invoke the function (for example C-u C-u M-x org-time-stamp-inactive RET)
The Emacs Help page for the function shell-command-on-region says (elided for space):
(shell-command-on-region START END COMMAND &optional OUTPUT-BUFFER
REPLACE ERROR-BUFFER DISPLAY-ERROR-BUFFER)
...
The noninteractive arguments are START, END, COMMAND,
OUTPUT-BUFFER, REPLACE, ERROR-BUFFER, and DISPLAY-ERROR-BUFFER.
...
If the optional fourth argument OUTPUT-BUFFER is non-nil,
that says to put the output in some other buffer.
If OUTPUT-BUFFER is a buffer or buffer name, put the output there.
If OUTPUT-BUFFER is not a buffer and not nil,
insert output in the current buffer.
In either case, the output is inserted after point (leaving mark after it).
If REPLACE, the optional fifth argument, is non-nil, that means insert
the output in place of text from START to END, putting point and mark
around it.
This isn't the clearest, but the last few sentences just quoted seem to say that if I want the output of the shell command to be inserted in the current buffer at point, leaving the other contents of the buffer intact, I should pass a non-nil argument for OUTPUT-BUFFER and nil for REPLACE.
However, if I execute this code in the *scratch* buffer (not the real code I'm working on, but the minimal case that demonstrates the issue):
(shell-command-on-region
(point-min) (point-max) "wc" t nil)
the entire contents of the buffer are deleted and replaced with the output of wc!
Is shell-command-on-region broken when used non-interactively, or am I misreading the documentation? If the latter, how could I change the code above to insert the output of wc at point rather than replacing the contents of the buffer? Ideally I'd like a general solution that works not only to run a command on the entire buffer as in the minimal example (i.e., (point-min) through (point-max)), but also for the case of running a command with the region as input and then inserting the results at point without deleting the region.
You are wrong
It is not a good idea to use an interactive command like shell-command-on-region in emacs lisp code. Use call-process-region instead.
Emacs is wrong
There is a bug in shell-command-on-region: it does not pass the replace argument down to call-process-region; here is the fix:
=== modified file 'lisp/simple.el'
--- lisp/simple.el 2013-05-16 03:41:52 +0000
+++ lisp/simple.el 2013-05-23 18:44:16 +0000
## -2923,7 +2923,7 ## interactively, this is t."
(goto-char start)
(and replace (push-mark (point) 'nomsg))
(setq exit-status
- (call-process-region start end shell-file-name t
+ (call-process-region start end shell-file-name replace
(if error-file
(list t error-file)
t)
I will commit it shortly.
If you follow the link to the functions' source code, you'll quickly see that it does:
(if (or replace
(and output-buffer
(not (or (bufferp output-buffer) (stringp output-buffer)))))
I don't know why it does that, tho. In any case, this is mostly meant as a command rather than a function; from Elisp I recomend you use call-process-region instead.
In my case (emacs 24.3, don't know what version you're using), the documentation is slightly different in the optional argument:
Optional fourth arg OUTPUT-BUFFER specifies where to put the
command's output. If the value is a buffer or buffer name, put
the output there. Any other value, including nil, means to
insert the output in the current buffer. In either case, the
output is inserted after point (leaving mark after it).
The code that checks whether to delete the output (current) buffer contents is the following:
(if (or replace
(and output-buffer
(not (or (bufferp output-buffer) (stringp output-buffer)))))
So clearly putting t as in your case, it is not a string or a buffer, and it is not nil, so it will replace current buffer contents with the output. However, if I try:
(shell-command-on-region
(point-min) (point-max) "wc" nil nil)
then the buffer is not deleted, and the output put into the "Shell Command Output" buffer. At first sight, I'd say the function is not correctly implemented. Even the two versions of the documentation seem not to correspond with the code.
Two questions:
Where does the result of eval-buffer get stored? How do I access it?
For example:
(+ 2 2)
Functions like (forward-word) are executed by eval-buffer, but do not move the cursor? Why is that?
eval-buffer is usually used for side-effects, rather than return value. For example, in your .emacs file, eval-buffer will re-load all our config settings. By default, and when used interactively, it will always return nil. If you want to get the return value of code in a buffer, this is the wrong way to do it. eval-last-sexp, bound to C-x C-e, is one way to do so. Calling it with a prefix, C-u C-x C-e will insert the return value into the current buffer.
eval-buffer preserves the value of point. So functions like forward-word will have no visible effect.
I want to copy a string to the clipboard (not a region of any particular buffer, just a plain string). It would be nice if it were also added to the kill-ring. Here's an example:
(copy-to-clipboard "Hello World")
Does this function exist? If so, what is it called and how did you find it? Is there also a paste-from-clipboard function?
I can't seem to find this stuff in the Lisp Reference Manual, so please tell me how you found it.
You're looking for kill-new.
kill-new is a compiled Lisp function in `simple.el'.
(kill-new string &optional replace yank-handler)
Make string the latest kill in the kill ring.
Set `kill-ring-yank-pointer' to point to it.
If `interprogram-cut-function' is non-nil, apply it to string.
Optional second argument replace non-nil means that string will replace
the front of the kill ring, rather than being added to the list.
Optional third arguments yank-handler controls how the string is later
inserted into a buffer; see `insert-for-yank' for details.
When a yank handler is specified, string must be non-empty (the yank
handler, if non-nil, is stored as a `yank-handler' text property on string).
When the yank handler has a non-nil PARAM element, the original string
argument is not used by `insert-for-yank'. However, since Lisp code
may access and use elements from the kill ring directly, the string
argument should still be a "useful" string for such uses.
I do this:
(with-temp-buffer
(insert "Hello World")
(clipboard-kill-region (point-min) (point-max)))
That gets it on the clipboard. If you want it on the kill-ring add a kill-region form also.
The command to put your selection on the window system clipboard is x-select-text. You can give it a block of text to remember. So a (buffer-substring (point) (mark)) or something should give you what you need to pass to it. In Joe's answer, you can see the interprogram-cut-function. Look that up for how to find this.
In my .emacs file, i use this
(global-set-key "\C-V" 'yank)
(global-set-key "\C-cc" 'kill-ring-save)
I could not use Ctrl-C (or System-copy), but this may be enough in case old habits kick in.
I want to copy a text from one buffer to another with text properties. So I have
(with-current-buffer from-buffer
(setq text-to-copy (buffer-substring beg end)))
How can I insert the text-to-copy to another buffer with all text properties? I'm interested especially in 'face' properties.
The function buffer-substring returns a list, for example ("substring" 42 51 (face font-lock-keyword-face) 52 59 (face font-lock-function-name-face))
If I pass this list to (insert text-to-copy) it seems that it ignores text properties
If font-lock-mode is turned on in the target buffer of insertion, the face property will be reset once the fontification kicks in. I think you'll need to either turn off font-lock-mode, or munge the text properties to replace 'face' with 'font-lock-face' before insertion.
The 'insert' function should handle strings that include text-properties, as-is. Since buffer-substring by default will return a string with text-properties if present, '(insert text-to-copy)' should be all you need to do.
If on the other hand you wanted to extract the string without the text-properties, you'd want to be using buffer-substring-no-properties instead
That should work. This is from Emacs 23.1.1:
buffer-substring is a built-in function in `C source code'.
(buffer-substring start end)
Return the contents of part of the current buffer as a string.
The two arguments start and end are character positions;
they can be in either order.
The string returned is multibyte if the buffer is multibyte.
This function copies the text properties of that part of the buffer
into the result string; if you don't want the text properties,
use `buffer-substring-no-properties' instead.
You can use the command describe-text-properties interactively to see what it is you actually got:
describe-text-properties is an interactive compiled Lisp function in
`descr-text.el'.
It is bound to <C-down-mouse-2> <dp>, <menu-bar> <edit> <props> <dp>.
(describe-text-properties pos &optional output-buffer)
Describe widgets, buttons, overlays and text properties at pos.
Interactively, describe them for the character after point.
If optional second argument output-buffer is non-nil,
insert the output into that buffer, and don't initialize or clear it
otherwise.