I am new to Isabelle/jEdit. I am accustomed to Emacs, so I'd like to set the shortcuts in Emacs style. It went well in most cases, but the command Emacs Set Mark does not work. When I invoke the command, the message "Input/output complete" appears in the minibuffer, and nothing happens in the text area.
Does anyone have an idea to fix it? I tried the various shortcut keys but all fail.
I use macOS Big Sur (version 11.5.2), Isabelle2021. (The keyboard is Japanese style.)
Both jEdit and the jEdit Isabelle plugin have a bunch of defaults which conflict with Emacs-style keys, so you have to make sure to unbind any existing keybindings that conflict with the ones you want to add and make sure they are removed from both primary and secondary. You have to do this by hand starting with the standard keybindings, because the Emacs keybinding set provided with jEdit sucks--and even worse, none of the default Isabelle keybindings are in it. Next time you start jEdit, it will open a dialog saying that there are keybinding conflicts, and you'll have to confirm the ones you just added.
Since this is kind of 面倒くさい both to explain and to do yourself, and there's not an easy way to show what I've changed vs. the defaults, here's my jEdit properties and Emacs-like keymap file. To use them:
Quit jEdit.
Copy the keymap file to $JEDIT_SETTINGS/keymaps/ (run isabelle getenv JEDIT_SETTINGS from your shell).
If you want to just use all my settings, copy the properties file to $JEDIT_SETTINGS/ (why wouldn't you, I have great taste :) ). Otherwise, grep -E '(^keymap\.current|\.shortcut2?\.ignore)=' properties and add the lines to $JEDIT_SETTINGS/properties yourself.
Start jEdit and resolve any keybinding conflicts it complains about.
My settings are Emacs-like with as many of the default Isabelle keys preserved, but Emacs stuff mostly takes priority: for example, Ctrl+b is backward-char instead of Isabelle completion, and Ctrl+e is move-end-of-line instead of being stolen by jEdit for a bunch of its key sequences.
Ctrl+SPC should activate the mark, but note that the region will NOT be highlighted until you perform some other command--try Emacs kill ring save (bound to M+w; that will probably be Opt+w on your Mac keyboard).
I haven't ran macOS in ages--I currently use Isabelle/jEdit on Linux over remote X11 with the X server running on Windows--but it shouldn't be any different on macOS, even with the Japanese layout, unless some other program you have is eating keys before they get to jEdit. (I think Ctrl+SPC switches the IME/keyboard layout on macOS by default, right? You might want to change either the macOS setting or the set mark binding in jEdit.)
On Java SE 16 and 17, you will probably get an error from jEdit saying something like:
unknown error: Unable to make public java.lang.AbstractStringBuilder java.lang.AbstractStringBuilder.append(java.lang.String) accessible: module java.base does not "opens java.lang" to unnamed module
To fix this, add this to your $ISABELLE_HOME_USER/etc/settings:
JEDIT_JAVA_OPTIONS="$JEDIT_JAVA_OPTIONS --add-opens=java.base/java.lang=ALL-UNNAMED"
(The --add-opens stuff is related to this Java runtime change, though you don't need to care about any of this to use Isabelle.)
Related
I am trying to use org-mode and whenever I press Crtl+return emacs does C-J instead. I know this because when I use c-h k and then press crtl+return, emacs shows:
"It is bound to C-j."
Is there anyway I can make it register ctrl+return so I can insert headings?
I am using emacs23 through the terminal on ubuntu 12.04 x64. When I do this on my windows machine it does insert a new heading.
Possibly. As #phils says, C-Enter is usually not a valid sequence for the vast majority of terminal emulators. This is because when you press a key, or key combination, the terminal sends a sequence of characters to the relevant application. Pressing a sends a, whereas Enter sends CR - carriage return (otherwise known as ^M, \r or \015).
What sequences are actually implemented in modern terminals is mostly just a hang-over from the earlier, physical, terminals that they emulate (notably the VT-100). These machines didn't allow the use of Ctrl in conjunction with every key, such as the function keys, for example, so C-F1 was not possible and didn't have an escape sequence defined. Similarly, there is no control sequence for C-Enter, so when you press it, the terminal ignores the Ctrl and just sees the Enter.
You may, however, be able to define your own escape sequences in your terminal, which you can then bind to the correct key combinations in emacs. See here, for example. I was able to use this method to be able to use C-Enter. Unfortunately, this is still a bit of a pain, as it requires a lot of configuration and you may still be unable to use some sequences (C-M-% doesn't work in konsole for me). As with #phils, I've taken to using the GUI, but I'd love to have better integration with my terminal.
That's not a valid sequence for most terminals, I'm afraid, so they simply can't send it to Emacs.
If you run GUI Emacs instead, the key bindings will work.
Thomas Dickey's xterm is the only terminal software I know of which can (I think) support all the normal Emacs bindings. If you're okay with compiling that, then you could try it with the following .Xdefaults-(hostname) (or .Xresources if you re-merge after editing) to get basic support working:
XTerm*metaSendsEscape: true
XTerm*modifier: meta
XTerm*modifyOtherKeys: 1
You actually need XTerm*modifyOtherKeys: 2 to fully extend the sequences (otherwise you still can't type the likes of C-M-%), but by default that setting will break most key sequences, and right now I couldn't tell you how to configure things correctly for that setting (the only example I've seen -- xterm-extras.el as mentioned on the wiki and available in the easymacs download -- didn't work for me).
I mostly use GUI Emacs, but I'd love to get this working properly, so if anyone has had success with xterm-extras.el or similar, please do speak up.
If you're willing to install an Emacs package and configure your terminal, I wrote an Emacs package which can teach Emacs and terminals how to properly recognize all PC keyboard keys and modifier key combinations:
https://github.com/CyberShadow/term-keys
Its default configuration enables encoding the CtrlReturn combination, which allows Emacs to distinguish it from CtrlJ.
I'm using emacs in the Linux console.
I would like to be able to use C-DEL(that is CtrlBackspace) to backwards-kill-word to have an interface that is consistent with the emacs gui - as well as most other interfaces on various platform.
C-DEL doesn't work to backwards-kill-word because the sequence for complicated reasons is interpreted as C-h as explained in this section of the emacs wiki.
How can I get C-DEL to delete a word back and maintain the default behaviour (help menu) for C-h?
Seemingly, this can't be fixed by way of configuring emacs but using showkey, loadkeys and dumpkeys to load a custom keymap where Alt+Backspace is bound to Meta_Delete (just like Ctrl+Backspace is by default) did the trick.
In Haskell-mode, the shortcut C-c C-= is defined to do something.
Trying this shortcut, I realized that emacs do not recognize the shortcut C-c C-=.
Indeed, when I try the shortcut on emacs, the buffer write C-c = is not defined although I pressed C- C-=. I have the same problem with some other symbols like '.' or '§'. But shortcuts like C-c C-l or C-c C-c work.
I try to remove my .emacs but I have the same problem.
a friend have the same problem as me.
Both we are on ArchLinux (64 bits) and we use emacs in console. The keyboard is an azerty.
The problem come from emacs ? Arch Linux ?
Your terminal can't send Emacs C-= so you can't use that key sequence. (Emacs would recognise it if it received it, but that won't happen.)
Your options are:
Run GUI Emacs.
Use M-x name-of-command RET (for whatever command is bound to the key sequence you're not able to use). Use C-hm to see the major mode's bindings, or C-hb to see all current bindings, in order to learn what those command names are.
Create new custom keybindings for the commands in question (i.e. bindings which your terminal can send to Emacs).
Find a different terminal emulator with enhanced key sequence abilities. The vast majority of them will be no better than what you have, because they're all adhering to the limitations of the terminals they're emulating. The most capable one I know of is http://invisible-island.net/xterm/xterm.html but you may need to compile it yourself, and then expect to spend lots of time configuring it. (It's not a trivial solution, though, and xterm requires a GUI environment, so running GUI Emacs is much simpler.)
Use C-x#c<key> instead of C-<key>.
With that last option, you can use a sequence your terminal can send to fake a sequence that it can't send.
C-cC-= would become C-cC-x#c=
If you really wanted to use that last option, you can set a custom binding to simplify the sequence (may be necessary in some instances to avoid conflicting with existing sequences). See the end of https://stackoverflow.com/a/24804434/324105 for more information.
To add to phils' post - another option is an Emacs package (which I wrote), which can teach Emacs and terminals how to properly recognize all PC keyboard keys and modifier key combinations:
https://github.com/CyberShadow/term-keys
The default configuration already includes encoding key combinations like Ctrl=, as well as similar variations.
I must be stupid, but I just switched to Emacs 24, and holding Shift while moving the point no longer highlights text. Mouse selection works as before. What am I missing? Did I turn it off by chance? Or has Shift selection been deemed unergonomical so we have some other, better keyboard-based selection at hand?
Shift selection is enabled by default in Emacs 24.
You can always run emacs -Q to disable your init file and any other default libraries, in order to determine what Emacs' default behaviour is.
You can also run emacs -q which will disable only your init file (other system-wide init files can be loaded).
If the feature works without your init file and does not work with it, you can then start to narrow down what part of your init file is at fault (often by commenting out functionality until the feature starts working as expected -- note Drew's comment).
In this case I suggest that you firstly verify (using C-hv) that the shift-select-mode variable is non-nil (when running with your normal configuration), as a nil value means that shift selection is disabled.
I also found it useful to look at load-path variable, C-h v load-path, which directed me to the culprits, old elpa packages.
I've found that terminal emacs does not render the correct colors unless I explicitly set TERM=xterm-256color. I use gnome-terminal, and from what I understand, TERM should be set to gnome-256color. Similarly, I tend to use tmux a lot, which advises against any TERM setting other than screen-256color. Unfortunately, both of those settings (within their respective context - gnome-terminal or tmux) result in emacs having wrong colors, whereas vim displays colors correctly. However, if I export TERM=xterm-256color, the colors work just fine in emacs.
Can anyone explain what's going on, or offer a solution?
Update
Here's what I'm dealing with:
I can get the colors to look correct in the terminal by adding the following to my init.el:
(defun terminal-init-gnome ()
"Terminal initialization function for gnome-terminal."
;; This is a dirty hack that I accidentally stumbled across:
;; initializing "rxvt" first and _then_ "xterm" seems
;; to make the colors work... although I have no idea why.
(tty-run-terminal-initialization (selected-frame) "rxvt")
(tty-run-terminal-initialization (selected-frame) "xterm"))
This feels really, really wrong though. There has to be a logical explanation for this...
P.S.
I have very little knowledge of terminfo and the precise role that $TERM plays in the process of color terminal behavior. If it's safe to always use xterm-256color (even when $TERM "should" be gnome-256color or screen-256color), I'll go with that.
Maybe I'm not understanding something, buy why don't you run emacs like this:
TERM=xterm-256color emacs -nw
This way Emacs has its own TERM setting that you know works. You can also make an alias or wrap this in shell-script.
Terminals are a special type of device. When a process sends special byte sequences (called control sequences) to the terminal, it performs some action (like cursor positioning, change colors, etc).
You can read the ANSI terminal codes to find more detail about control sequences.
But terminals come from 70s, when hardware was limited in its capabilities, and a terminal cannot provide info about its capabilities (ie. which sequences it supports).
$TERM was used to resolve this issue - it allows programs to know what to send to the terminal to get the job done. termcap and terminfo are databases that store info about terminal capabilities for many $TERM names. If your $TERM is not in the db, you must ask an administrator to add it.
All terminal emulators inherit these limitations from old hardware terminals. So they need a properly set $TERM, and the terminfo/termcap DB MUST have data for this terminal. When a virtual terminal starts it sets the $TERM variable for you (and inside programs like bash). If $TERM is not in the terminfo/termcap you can quickly define an alias from $TERM to xterm-256color (you can find examples in the termcap file on how to do that).
This behavior has to do with the logic EMACS uses to determine whether the terminal background is dark or light. Run M-x list-colors-display with TERM set to either xterm-256color or screen-256color and you'll see that the exact same colors are listed. As you pointed out in the comments, the difference in color schemes that you've observed is due to the frame background mode. To see this, with your TERM set to screen-256color, compare the colors in
emacs -Q -nw --eval "(setq frame-background-mode 'light)"
and
emacs -Q -nw --eval "(setq frame-background-mode 'dark)"
The function frame-set-background-mode (in frame.el) checks to see whether the terminal type matches "^\\(xterm\\|\\rxvt\\|dtterm\\|eterm\\)" if it can't deduce the background color otherwise.
Within a running session, you can change the color scheme to 'light by evaluating
(let ((frame-background-mode 'light)) (frame-set-background-mode nil))
I am not that familiar with how emacs handles different terminals exactly. But looking at lisp/term directory in emacs sources, I found out that the existence of a function terminal-init-xxx allows you to add support for different terminals. For example, I've got:
(defun terminal-init-screen ()
"Terminal initialization function for screen."
;; Use the xterm color initialization code.
(xterm-register-default-colors)
(tty-set-up-initial-frame-faces))
in my .emacs, which adds support for screen-256color. You may try defining a similar function for gnome by renaming the above function to terminal-init-gnome.
NOTE: If you are interested, you can try to track down the calls from tty-run-terminal-initialization code. It first gets the terminal type using tty-type function, then looks at certain locations to load a relevant terminal file, then tries to locate the matching terminal-init-xxx function, and finally calls it. It may help you figure out the correct name for gnome-terminal.
It looks like unless your TERM indicates that your terminal has 256 colors, emacs will only use 8. Changing TERM to gnome-256color allowed the color registration functions to work.
There is a way to cheat, after all. When I run gnome-terminal, my terminal is set to xterm by default. Instead of changing TERM variable, it is possible to redirect xterm to another terminal, say, gnome-256color. Simply create the directory $(HOME)/.terminfo/x, then run ln -s /usr/share/terminfo/g/gnome-256color ~/.terminfo/x/xterm. I think this is better than setting TERM manually in .bashrc, because it only redirects a particular terminal to something else. A console login would still leave TERM as linux, and not xterm-256color.
Add this to your ~/.emacs:
(add-to-list 'term-file-aliases
'("st-256color" . "xterm-256color"))
It tells emacs that if it sees TERM=st-256color then it should initialize the terminal as if it had seen TERM=xterm-256color.
Longer answer:
Emacs is showing strange colors because it thinks your terminal can only support 8 colors. In Emacs, run M-x list-colors-display to see the colors it thinks are available. The correct number of colors is detected during terminal-specific initialization. It says, in part:
Each terminal type can have its own Lisp library that Emacs loads when run on that type of terminal.
On my machine, the terminal-specific initialization files are in /usr/local/share/emacs/25.*/lisp/term. It has files for xterm, rxvt, screen, etc. but nothing for st. We need to help Emacs find the right initialization file. The documentation further says:
If there is an entry matching TERM in the term-file-aliases association list, Emacs uses the associated value in place of TERM
So that association list is a recommended way to handle unknown terminals. It works without you having to manually override the TERM environment variable.
On ubuntu 10.04 I too had noticed that running emacs -nw inside byobu/tmux/screen was using different colours from emacs -nw in the regular gnome-terminal.
I found that this is because byobu was setting TERM to screen-bce. Then setting TERM to xterm (for me, in the normal gnome-terminal TERM=xterm) gave me the same syntax highlighting when not running through byobu/screen.
So still not sure what the proper solution is.
See also this post:
Emacs Python-mode syntax highlighting