I have installed Emacs on my FreeBSD 8.2 box. Everything works fine but I cannot use tabs. When I am editing a file with emacs and hit tab, nothing happens.
What could be causing this?
If you're new to Emacs, you might expect pressing TAB to insert a literal \T. For various reasons, that's not the way most Emacs modes work. Most editing modes auto-indent your code as needed (<tab> is bound toindent-for-tab-command rather than self-insert). If the line you're TABbing on is already at the correct indentation level, it might seem that nothing happened.
Auto-indenting like this is easier and more consistent than manually indenting, but doesn't give you as much flexibility when it comes to deciding exactly how much whitespace is going to be present at the beginning of each line (and it also causes some problems when you want to, for example, tab-separate some fields). You can auto-indent a region using C-M-\ (that's Ctrl + Alt + \).
If you absolutely, positively must insert a literal \T into your code somewhere, you can do so using C-q TAB (press and release Ctrl + q and then press TAB). Typically, this is done to align columns in other editors; if that's what you're doing, it's probably a better idea to use align-regexp rather than tab literals.
In fundamental and text-mode I use C-<TAB>. I do not know which other modes this works in, but with few exceptions, plain text is the only time I need an actual \t character.
Related
By default, Emacs 24 can handle Arabic, Hebrew, and other right-to-left (RTL) languages. I have multilingual term emulators that handle this in X, but I would like to use eshell inside emacs to see the non-English character filenames (and boy do I have many). When I use eshell, the characters are not in the correct order and it spells out gibberish. (setq-default bidi-display-reordering t) (which is default) makes no difference obviously.
Is this possible?
I believe you're getting double reordering by emacs + mlterm, and need to disable one.
Your screenshot shows in upper half mlterm successfully detects line-by-line base direction and reorders characters.
And Emacs 24 by default reorders bidi in the terminal, assuming a non-bidi LTR termianl.
Combining both results in double reordering ABC -> CBA -> ABC.
You have 2 options:
Disable bidi in mlterm (at least while running emacs, not sure how to automate that).
Disable bidi in emacs (at least when running under mlterm).
I.e. set bidi-display-reordering to nil, not t.
I expect the first will work better. mlterm can only give you a dumb "bidi display" layer, which may be confusing on top of an editor; emacs gives you "bidi editing" where someone thought of how the whole interaction should work.
Specifically, side-by-side "windows" within emacs should work well when emacs is doing the bidi and break horribly when mlterm is.
OTOH, mouse copy-paste probably works better when mlterm is doing the bidi.
If emacs sends reordered chars, that's what mlterm mouse selection will copy.
Emacs can mostly take over mouse with xterm-mouse-mode but (untested speculation) it works on terminal coordinates and would need extra work to match them to logical-order text.
P.S. I'm not sure why the end result is right-aligned, as it seems there is a blank line before so Emacs should consider it a new paragraph, decide it's RTL and send right-aligned text to mlterm, and I'd expect mlterm to then reverse the line resulting in it left-aligned. I'm probably missing something.
In emacs (ver. 24.3), I have my forward-paragraph and backward-paragraph mapped to M-p and M-n instead of M-{ and M-}. It is easier for me to remember and use fluidly with C-p and C-n. I've recently started using multi-term to run most of my terminal work. However, when I switch to line-mode my custom bindings for forward and backward paragraph no longer work. It says 'empty input ring'. Oddly when I'm in char-mode, the C-p and C-n do what they are supposed to do (bringing up previous prompt entries), but my paragraph movements work.
So in short, my custom forward and backward paragraph bindings work in char-mode (where I don't really need them), but not in line-mode. Any ideas?
See term-bind-key-alist, which includes C-p, C-n, M-p, and M-n by default. See also these passages from the EmacsWiki page MultiTerm. The second especially seems relevant to your problem. These do not mention term-line-mode or term-char-mode, but I think they might give you a place to start.
Note 1
‘term-unbind-key-list’ is a list of keys which emacs keeps for itself. By default it contains (“C-z” “C-c” “C-x” “C-h” “C-y” “”)
‘term-bind-key-alist’ is a list of keys and functions which you can use, for example to use Emacs style cursor movement to the multi-terminal. The default is long, so I’ll let you look it up yourself.
Note 2
Because C-r is default keystroke for isearch-backward, for avoid conflict with C-r, i binding M-r to send “C-r” character to shell.
You can use option term-bind-key-alist/term-unbind-key-list to binding/unbinding special keystroke in multi-term.el, and don’t use term-mode-hook. ☺ –- AndyStewart
Also, I don't see term-line-mode anywhere in multi-term.el. It looks as if it makes use only of term-char-mode. See, for instance, multi-term-keystroke-setup.
I'm a beginner with emacs. Altough I'm finding it amusing and challenging, I still don't know some basic things, like, when I open a text or a piece of script wrote in another editors, emacs don't show the text formatted properly (missing all tabs, all text left-aligned) and vice-versa.
Also, when I copy a link with emacs with M-w, my clipboard is still empty and I can't paste it in a browser. I already did my "homework". I've read the tutorial and I'm almost finishing the manual and didn't see anything to address that.
tnx in advance.
Some editors, like Intellij IDEA for example, will indent code based on how they understand it and not based on how it was actually indented, there's no Emacs mode that operates in the same way, not to my best knowledge. If you were using something like Eclipse or MS Visual Studio before - then you probably just have a different size of tab character (this is why some programmers insist on indenting code with spaces rather than tabs). But the width of the tab character is adjustable. In order to customize it you would:
add in your initialization file (usually .emacs file in your $HOME directory, you can create one, if it is not there yet):
;; makes tab character as wide as four space characters
(setq default-tab-width 4)
though some other major editing modes override this variable, you would need to tell what language you are dealing with to get better instructions.
Clipboard, see this answer: How to copy text from Emacs to another application on Linux if you are on Linux, then likely you need to set x-select-enable-clipboard to t.
Aligning text to the right (or left for LTR languages) is not possible in Emacs, as far as I understand. You could align block of text, if you split it into lines and align on the line ends, but that would mean aligning by adding spaces at the beginning - something you don't really want to do.
Tabs should work (you might need to fix the width). Use mouse to select to the clipboard, or use CtrlInsert to copy and ShiftDelete to cut.
Assuming emacs has picked the right mode for the file - it usually does - you can press C-x h to select all, then TAB to indent all selected lines. What other editors are you using, and what platform(s)?
As for the clipboard issue, some builds of emacs work correctly with the native clipboard, some don't. You might want to investigate CUA mode.
I decided that I was ready to try something new, after a few years of using gEdit for most of my coding needs, and try to learn using Emacs. I knew this would be difficult, as I have heard how complex Emacs can be, but I was lured by its power. The hardest thing has been getting used to writing ELisp in the .emacs file to change things about the editor. I can't currently do it myself, but I have found a few helpful snippets here and there to change some options.
One thing I have been having a lot of problems with is getting Emacs to remember the text I have selected after a command. For instance, I commonly highlight a section of code to mass indent it. However, if I do this in Emacs, it will move the selected text only once before unselecting all of the text. Does anyone know a way around this?
Anyway, I apologize for what seems to me to be an easy question, but after an hour of Google searching and looking around here on SO, I thought it was worth asking. I have a few more questions about Emacs, but I will save them and ask separately after I get this straightened out. Thanks!
UPDATE
A few people have asked about what mod I am using and what type of text I am entering. While I don't know much about Emacs modes, I am editing a pure text file at the moment. Something like this:
Hello, I am a simple text file
that is made up of three separate
lines.
If I highlight all three lines and hit TAB, I get this:
Hello, I am a simple text file
that is made up of three separate
lines.
This is great, however, if I use C-x C-x like some suggest below to reselect the text and hit TAB again, I get this:
Hello, I am a simple text file
that is made up of three separate
lines.
I hope this helps!
FWIW, here is the reason for the behaviour of your newly-added example. (I'm not 'solving' the issue here, but I'm posting it to demystify what you're seeing.)
This was determined with emacs -q which disables my customisations, so the following is default behaviour for emacs 23.2.
You are in text-mode. You should see (Text) or similar in the mode line at the bottom of the screen, and C-h m will tell you (under the list of minor modes) "Text mode: Major mode for editing text written for humans to read." Emacs decides (by way of the auto-mode-alist variable) that it should switch to text-mode if you visit a filename matching certain extensions (such as .txt).
In text-mode pressing TAB with a region highlighted causes indent-according-to-mode to be called on each line of the region in sequence. The slightly convoluted path to finding this out starts at C-h k TAB, which tells us that TAB is bound to indent-for-tab-command, which in this instance calls indent-region -- that function name is not stated explicitly in the help, but can be seen in the code -- which checks the buffer-local indent-region-function variable, which is nil, and: "A value of nil means really run indent-according-to-mode on each line."
indent-according-to-mode checks the indent-line-function variable, which has the buffer-local value indent-relative.
Use C-h f indent-relative RET to see the help for this function. (Read this).
Although you probably won't yet have had the experience to know how to check all that (or necessarily even want to!), and fully understand everything it tells you, this is an example of how the self-documenting aspect of Emacs enables a user to figure out what is going on (which then makes it feasible to change things). I essentially just used C-h k (describe-key), C-h f (describe-function), and C-h v (describe-variable) to follow the documentation. Looking at the source code for indent-for-tab-command was as simple as clicking the file name shown as part of its help page.
I suggest doing the following to help see what is happening when indent-relative runs on each line:
M-x set-variable x-stretch-cursor t
M-x set-variable ruler-mode-show-tab-stops t
M-x ruler-mode
Now for each line in turn, put the cursor at the very start of the line and press TAB. You'll end up with all three lines indented to the first tab-stop ('T' in the ruler).
Now repeat this -- again, ensure you are at the very start of each line, in front of the existing indentation.
The first character of the first line (which is currently a tab) is once again indented to the first tab-stop, as there is no preceding line for it to examine.
Next, the first character of the second line is indented to match the position of the first non-white-space character of the preceding line. Because the first character of the second line is also a tab, the actual text of the second line is pushed one tab further along.
The third line follows suit. Its first tab character is lined up with the first non-white-space character of the second line, with the same relative effect as before, giving you the final state in your example.
To emphasise, note what happens if you now put enter the line "a b c" above the existing lines, then move back to the start of the next line (what was previously the first line) and press TAB. The first tab character will now be indented in line with the 'b'. Provided that the indent-tabs-mode variable is true (meaning you have actual tab characters), then this will have no practical effect on the position of the words in the line, as 'indenting' a tab with spaces will not have an effect until the number of spaces exceeds the width of the tab (but that's another kettle of fish entirely!)
All this really means is that text-mode in Emacs doesn't behave the way you'd like it to in this situation. Other major modes can do completely different things when you press TAB, of course.
As is invariably the case with Emacs, things you don't like can be changed or circumvented with elisp. Some searching (especially at the Emacs Wiki) will frequently turn up useful solutions to problems you encounter.
Try typing C-x C-x after Emacs unselects it.
Then, instead of hitting tab (I never knew that tab does what you said! That's totally whacked.), do M-8 C-x C-i. Pity it's so many keys, but it ought to do what you want -- namely, shove everything over 8 columns. Obviously replace the M-8 with something else if you want some other number of columns.
What I usually do is simply type C-x C-x (exchange-point-and-mark) after a command that deactives the region.
How are you indenting, and in which mode?
The indentation rules in any programming mode should generally just get it right. (If they don't, that's probably more indicative that you want to configure the rules for that mode differently, but I suspect that's a different question which has been asked already).
If you're in text-mode or similar and just using TAB, then I can see the problem.
Note that if you're using indent-rigidly (C-x C-i, or C-x TAB which is the same thing) then you can repeatedly indent the same region simply by repeating the command, even if the highlighting has disappeared from view.
You can also use a prefix arg to indent-rigidly to make it indent many times. e.g. C-u C-u C-x C-i (easier to type than it looks) will indent 16 spaces (4 x 4, as the prefix arg defaults to 4, and it multiplies on each repeat). Similarly, M-8 C-x C-i indents 8 spaces. This is fine in some circumstances, and way too cumbersome in others.
Personally I suggest putting (cua-selection-mode 1) into your .emacs and using that for rigid indentation. Trey Jackson made a handy blog about it. With this, you can C-RET to start rectangle selection, down as many lines as you need, TAB repeatedly to indent the lines, and C-RET to exit the mode.
While the rectangle is active, RET cycles through the corners. For left-hand corners, typing inserts in front. For right-hand corners, typing inserts after. For the single-column rectangle, bottom counts as 'left' and top counts as 'right' for this purpose.
Trey's blog lists all the available features (or look in the source file: cua-base.el)
Be warned that indentation in Emacs is generally an unexpectedly complicated topic.
You can do this with something like the following:
(add-hook 'text-mode-hook (lambda ()
(set (make-local-variable 'indent-region-function)
(lambda (s e)
(indent-rigidly s e tab-width)))))
Then selecting a region and hitting TAB. will indent the region by a tab-width. You can then exchange point and mark with C-x C-x and hit TAB again to repeat.
I do, however, agree with the previous answers that suggest using indent-rigidly directly.
Emacs reindents the current line whenever I type certain things, like ";" or "//". This is pretty annoying, since there are a whole lot of places where it isn't smart enough to indent correctly.
How do I disable this feature? I still want to be able to indent the line with TAB, but I don't want any source code I type to cause it to reindent.
(I'm using Dylan Moonfire's C# mode, but this probably applies to any cc-mode.)
Try running c-toggle-electric-state to turn off the electric action of these characters.
You can do this as part of a c-mode-common-hook, or toggle the state manually by hitting C-c C-l.
most likely caused by the inline-and-indent 'feature' of c-mode and derivatives. emacswiki has several solutions.