How to stop ipython autocompletion to generate a space at the end? - ipython

When using ipython in a console interactive session, pressing tab will generate autocompletions, but always generate an additional space character after the text. Can I change this behavior and make the autocompletion only generate the remaining text for the word?

This is a known and still-active bug Issue42

Related

Powershell 7.3.0 Tab completion not working

I've recently upgraded PowerShell to version 7.3.0 version and now, when I type a command, I see its suggestions like when I'm typing pip it adds list like in this image. Or when I type start of the command it suggests its full name.
The problem is that when I press Tab it doesn't complete the command, instead it just starts listing current directories, i.e. here is an image after pressing Tab once.
Also even when I start typing the full name of the command like pip li it still shows the ending, but when pressing Tab it just does nothing.
I expected this to complete the current command with the suggestion after Tab is pressed.
I've tried to google this problem but haven't found the exact same case I have with 7.3.0 version.
Just press -> (right arrow) key
If you want to change key bindings:
source: https://devblogs.microsoft.com/powershell/announcing-psreadline-2-1-with-predictive-intellisense/
Key Bindings for Predictions
Key bindings control cursor movement and additional features within the prediction. To support users running Predictive IntelliSense on multiple platforms, key bindings are user-settable from the command line or your profile script.
PSReadLine contains functions to navigate and accept predictions. As an example, to accept a displayed prediction, PSReadLine contains functions:
AcceptSuggestion – Accept the current inline suggestion
AcceptNextSuggestionWord – Accept the next word of the inline suggestion
AcceptSuggestion is built within ForwardChar, which by default is bound to RightArrow. Pressing RightArrow accepts an inline suggestion when the cursor is at the end of the current line.
AcceptNextSuggestionWord is built within the function ForwardWord, which can be bound with Ctrl+f by Set-PSReadLineKeyHandler -Chord "Ctrl+f" -Function ForwardWord. Pressing Ctrl+f accepts the next word of an inline suggestion when the cursor is at the end of current editing line.
As a user, you can bound other keys to AcceptSuggestion and AcceptNextSuggestionWord for similar functionalities. Search for ForwardCharAndAcceptNextSuggestionWord in SamplePSReadLineProfile.ps1 for an example to make RightArrow accept the next word from inline suggestion, instead of the whole suggestion line.
List of additional suggested key bindings defined in PSReadLine SamplePSReadLineProfile.ps1

Convert greek latex symbol in the jupyter-lab text editor

In Jupyter Notebooks you can type, for example \alpha and hit the tab key and the \alpha changes into α. This is a pretty cool feature. Unfortunately, it doesn't work in the jupyter-lab editor. Any reason why that doesn't work? Or do I need to set a preference somewhere?
if you type $\alpha$ it will be rendered as the greek letter thanks to latex
Although the answer of #joelostblom works fine, you can simply install the LaTeXStrings Julia package to enable the \alpha [tab] feature without needing to spawn an IPython kernel.
using Pkg
Pkg.add("LaTeXStrings")
This feature is provided by the IPython kernel, not the Jupyter Notebook. The kernel provides TAB completion by looking up the latex (or latex-like) symbol in this dictionary (originally from Julia) and then inserts its value (the corresponding Unicode character). As such, there needs to be an active IPython kernel to provide the TAB completion (here is the PR that added the functionality to IPython in case you want to read more about it).
An IPython kernel is automatically started with the notebook and used when running cells, but this is not the case when editing a text file (which is also why there is no TAB completion for other things such as imports, etc). You can start one manually by right clicking inside a Python text file and selecting "Create console for editor". After that autocompletion works just as in the notebook, including Greek latex symbols.

How to fix some tmux things (screen instead of xterm; function keys)?

Why does tmux change the terminal from xterm to screen, and how can I fix the resulting text color change in emacs? I think the easiest way would be to prevent it from changing to screen in the first place.
I can use TERM=xterm emacs file.ext to do it temporarily, but that's just a workaround that doesn't solve the root of the problem.
Furthermore, the function keys no longer work in emacs when using tmux. Instead of F3 and F4 being macro shortcuts, they just print a tilde as they would in the shell. This seems unrelated to xterm/screen mentioned above. What is happening here, and how I can fix this?
tmux sets TERM to screen because that terminal description is limited to things that tmux knows how to work with. Like screen, tmux translates features from the outer terminal description to the inner.
If a special key (function-key, cursor-key, etc) does not have an exact match in the terminal description, tmux will ignore it.
The default configuration for PuTTY sends different escape sequences for F1-F4. The sequences which PuTTY sends are not in the terminal description for xterm.
Here's a comparison of the two (as a CSV file, but readable enough):
NAME,putty,xterm
kf1,\E[11~,\EOP
kf2,\E[12~,\EOQ
kf3,\E[13~,\EOR
kf4,\E[14~,\EOS
kf5,\E[15~,\E[15~
kf6,\E[17~,\E[17~
kf7,\E[18~,\E[18~
kf8,\E[19~,\E[19~
kf9,\E[20~,\E[20~
kf10,\E[21~,\E[21~
kf11,\E[23~,\E[23~
kf12,\E[24~,\E[24~
kf13,\E[25~,\E[1;2P
kf14,\E[26~,\E[1;2Q
kf15,\E[28~,\E[1;2R
kf16,\E[29~,\E[1;2S
kf17,\E[31~,\E[15;2~
kf18,\E[32~,\E[17;2~
kf19,\E[33~,\E[18;2~
kf20,\E[34~,\E[19;2~
You'd have trouble getting PuTTY to send F13-F20, but will certainly run into trouble using PuTTY and tmux with TERM=xterm.
Regarding colors, the same issue applies. The screen terminal description tells applications that the terminal can support 8 colors, and tells how to display those eight colors. If your external terminal can do more, then tmux and screen hide that.
The conversion is not perfect. GNU screen has a feature where it looks for a corresponding screen.$TERM terminal description (i.e., concatenating the outer TERM value to screen). tmux does not do that: it makes assumptions regarding xterm. But PuTTY is not xterm...
ncurses has several of those concatenated terminal-names for terminal descriptions, but no one has suggested a way for tmux to use them automatically.

Ansi-coloured file editing

Context
Have some transcript files from terminal interaction, obtained using traditional Unix command "script".
Those transcripts contain lots of control character (like backspace when editing shell commands), and lots of color code sequences as result of running various commands. Occasionally, even colorful full-terminal (ncurses-based) applications like "emacs -nw" or "aptitude" were run.
At program runtime, TERM environment variable was set as "xterm".
Need 1: read (more or less solved)
I need to read those files again and sometimes copy-paste some small parts.
The trouble is : while one color change here and there is not so much of a problem, their actual density makes the output barely readable. Worse, edited command lines (with cursor jumps and edited words) are completely unreadable.
"Okay" solution
Browse through files using e.g. "less -r". Paging forward in the same terminal setup reproduces the various color and character style.
But many other features come out more or less broken, e.g. search backwards produces jumbled terminal output, often have to pres "Ctrl-L" to clean thing up.
Need 2: editing
My preferred editor is emacs. Some people have had a similar situation when running the shell inside emacs, e.g. Something wrong with Emacs shell.
Here is not the same situation. Examples of differences: here we don't have to run an actual shell, but we need to move cursor freely like in usual editing.
Editing here means easily open such a transcript file in editor and then:
at all times through editing, see character changes (color, attributes) as conveyed by the terminal codes
(optional) some character that are neighbour on the terminal grid but are separated in file by some control characters would have a visual hint about this
ability to insert some text,
delete sections,
use all editor features like search/replace etc.
copy & paste to & from file (including to external programs, which would receive just plain text)
in my wildest dreams, some kind of "flatten" action, like select a sequence with a heavily edited command line and replace it with a simple series of characters as if it was typed in one run. "Visual hints" mentioned above would disappear.
Type Alt-: to evaluate something in the minibuffer. Evaluate (ansi-color-apply-on-region (point-min) (point-max)) and it will convert ansi color codes to be font colors.

Emacs - How to keep text formatted to other editors?

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.