I am using the Rust extension on vscode and NOT rust-analyzer. However, when I am saving a file, vscode is using rustfmt to format my file but it doesn't automatically insert semicolons. I have a trivial function like this
fn call_me() {
let x = 5
println!(x)
}
It doesn't add the necessary semicolons. How do I make it add semicolons? Are my installations somehow messed up?
Also, I have tried rust-analyzer and it doesn't add semicolons either.
Unlike JavaScript, semicolons are not syntactically optional in Rust. Thus, leaving them out is a syntax error, not just a matter of style, and rustfmt (the standard Rust code formatting tool) doesn't ever attempt to fix any syntax errors, no matter how “obvious” they might be — if it reads a file with errors it will not make any formatting changes.
(I don't know if there's a way to get rust-analyzer, vim, or VS Code to auto-insert semicolons as a matter of editing rather than formatting.)
Maybe not what you're looking for but there are language-agnostic options to reduce the friction of semicolon insertion.
For instance the vs code extension colonize adds the shortcut alt+enter which appends a semicolon and newline, no matter where in the line the cursor is.
The GNU APL documentation on the line editor seems to assume one already knows how to use it. I only see mention of what commands/syntax '... are not fully supported in GNU APL'.
Compare with the documentation of Dyalog's APL ∇-editor, or MicroAPL.
I'd be willing to prepare a patch to submit for the documentation if anyone has a reference.
The main developer of GNU APL, Jürgen Sauermann, has told me that GNU APL's editor is a clone of APL2's line editor, and thus should support the same commands:
command
action
[⎕]
display the current whole definition
[⎕2 7 1 …]
display specific lines
[⎕2-7]
display a range of lines
[⎕-7]
display all lines until a specific line
[⎕7-]
display all lines beginning with a specific line
[7] code
replace a specific line
[2.1] code
insert a line between two lines
[∆2 7 1]
delete specific lines
[∆2-7]
delete a range of lines
[∆-7]
delete all lines until a specific line
[∆7-]
delete all lines beginning with a specific line
[→]
quit without saving
[2⎕7]
display line 2 for editing, placing the cursor at position 7
[2⎕0]
display line 2 for editing, placing the cursor at the end of the line
Source: IBM's APL2 Language Reference
See:
APL: The Language and Its Usage;
Polivka & Pakin;
1975
How can I automatically hard wrap lines in VSCode? By that I mean if a line reaches a specified column, automatically insert a newline at the word boundary closest to that column without going over. Vim has a setting called textwidth that does this that I like to use when editing Markdown. It doesn't seem like VSCode does, as far as I can tell. It just has ways to control softwrapping.
VSCode doesn't support this out of the box. But you can install the Rewrap extension, which allows you to format the block that your cursor is currently in by pressing Alt + Q.
Rewrap requires no further settings, since it reads VSCode's settings to obtain the column at which to break.
Rewrap also supports automatic wrapping (off by default): https://github.com/stkb/Rewrap/wiki/Auto-wrap
Unfortunately, VSCode doesn't have this feature yet. But, we still can make it to be as close as vim automatic word wrapping beautiful feature.
First Step
We need to setup soft word wrap feature in VSCode.
Open VSCode Settings via Code => Preferences => Settings.
Add these 3 lines of editor settings.
"editor.wordWrap": "wordWrapColumn",
"editor.wrappingIndent": "same",
"editor.wordWrapColumn": n
Don't forget to change (n) with your preferred length of columns line. For me, I feel more comfortable to set it to 60.
Save this setting.
The main purpose of this first step is to make us feel more comfortable when we're typing because we don't need to manually type Enter and see a long line of text.
Second Step
We need to install Vim emulation for VSCode and set vim textwidth.
Install Vim emulation via VSCode extensions.
Open VSCode Settings via Code => Preferences => Settings.
Add this line of vim setting.
"vim.textwidth": n,
Don't forget to change (n) with your preferred length of columns line. For me, I will set this to be the same with (n) in the first step.
Save this setting.
Actual Use
When you finish to write your whole document, you can format it to be hard wrap lines using this way.
Block all text using visual line mode (Shift + v)
Type 'gq'
Now VSCode support auto "soft" wrapping out of the box.
Settings --> Text Editor --> Last 3 options (as on today) is for autowrapping.
Word Wrap (Controls how lines should wrap)
Word Wrap Column (Controls the wrapping column of the editor)
Wrapping indent (Controls the indentation of wrapped lines)
By default Word Wrap is off.
As of 2020 and if you're using the Prettier - Code formatter plugin:
Go to Plugins -> Find Prettier -> Cog -> Extension Settings -> Prettier: Print Width Fit code within this line limit and set to whatever you want. By default it's 80.
When you save the file, Prettier will format automatically.
Hard Wrap Comments
Use the Rewrap extension.
Soft Wrap Code
Add the following setting (replace column width with your preference): "editor.wordWrapColumn": 100
Then add either "editor.wordWrap": "wordWrapColumn" (wraps at the column) or "editor.wordWrap": "bounded" (wraps at either the column or the viewport).
Hard Wrap Comments and Soft Wrap Code
Unfortunately the extension and VSCode settings do not play nicely.
Feel free to upvote this feature request.
There is currently an Open request for this in the VS Code Issue tracker on GitHub, You Can Find It Here
Most of these didn’t work for me, but I found the extension Vsctoix, which does.
We start out with line breaks at column 80:
Mechanisms such as a “windfall clause” help distribute riches within particular
futures. But for a windfall clause to be useful, many conjunctive assumptions
have to be true. We present a new method to borrow against potential future
windfalls today, when they have greater marginal use. The method also increases
the probability and thus the expected value of the windfalls.
Then we execute “IX: Join Lines” (no parameter):
Mechanisms such as a “windfall clause” help distribute riches within particular futures. But for a windfall clause to be useful, many conjunctive assumptions have to be true. We present a new method to borrow against potential future windfalls today, when they have greater marginal use. The method also increases the probability and thus the expected value of the windfalls.
And then “IX: Break Line At” with parameter 100:
Mechanisms such as a “windfall clause” help distribute riches within particular futures. But for a
windfall clause to be useful, many conjunctive assumptions have to be true. We present a new method
to borrow against potential future windfalls today, when they have greater marginal use. The method
also increases the probability and thus the expected value of the windfalls.
It would be neat if it respected paragraph breaks and did both steps at once, but so far it’s the only extension that works for me – except I haven’t tried the vim emulation yet.
You can do this without any extension. You just use two regex search-and-replace.
Isolate the lines you want to rewrap by moving them to a separate file.
Join all the lines into one line. For example, ctrl+h, "\n" ==> " ". Note: make sure regex is enabled (the dot star icon)
Split the line into multiple lines. For example, ctrl+h, "(.{100}) " ==> "$1\n". Notice the space after the paren.
Copy the lines back to the original file.
There are many variations on this technique. For example, you could using comma instead of space "(.{100})," ==> "$1,\n". You could use Find in Selection alt+L instead of using a temp file.
Edit: (below answer might be for a soft wrap, see here for difference between soft and hard wrap: https://stackoverflow.com/a/319932/9481613)
In my version it is Preferences -> Settings then scroll down to "Editor: Word Wrap" where a dropdown box is available from which I selected wordWrapColumn. After choosing this and closing, when I click on View now at the bottom it says Word Wrap Alt+Z.
If anyone is running having issues, accessibility support/screen reader may need to be disabled. Go to preferences >> text editor >> accessibility support and toggle it off.
You can easily set the column limit using ColumnLimit member in C_Cpp.clang_format_fallbackStyle in settings.json (You have to install Microsoft C/C++ extension)
"C_Cpp.clang_format_fallbackStyle": "{ BasedOnStyle: WebKit, IndentWidth: 4, ColumnLimit: 80 }",
Then you can format the file using Shift + Alt + F
There are many options you can change in this format feature
"C_Cpp.clang_format_fallbackStyle": "{ BasedOnStyle: WebKit, UseTab: Never, IndentWidth: 4, TabWidth: 4, BreakBeforeBraces: Attach, AllowShortIfStatementsOnASingleLine: false, IndentCaseLabels: false, ColumnLimit: 80, AccessModifierOffset: -4 }",
Name of the predefined style used as a fallback in case clang-format
is invoked with style file but the .clang-format file is not found.
Possible values are Visual Studio, LLVM, Google, Chromium, Mozilla,
WebKit, Microsoft, GNU, none, or use {key: value, ...} to set specific
parameters. For example, the Visual Studio style is similar to: {
BasedOnStyle: LLVM, UseTab: Never, IndentWidth: 4, TabWidth: 4,
BreakBeforeBraces: Allman, AllowShortIfStatementsOnASingleLine: false,
IndentCaseLabels: false, ColumnLimit: 0, AccessModifierOffset: -4,
NamespaceIndentation: All, FixNamespaceComments: false }
Before
void Proc::Memory::getSramOff(const char* mem_name, uint dataSize, uint addrBits, uint& noOfBytes, uint& sram_off)
After
void Proc::Memory::getSramOff(const char* mem_name, uint dataSize,
uint addrBits, uint& noOfBytes, uint& sram_off)
I'm quite new to cc-mode and I'd like to configure it to allow me to freely format and use tabs in multiline comments. This is important to me because I want to use cog.py in my source file and need to be able to format the python source in the comment correctly. I'd be ok with comments not beeing autoindented at all, however I'd like to keep auto indenting the rest of the source code.
Example:
...
/*
[[[cog
import cog
for x in ['a','b','c']:
>cog.outl(x)
]]]
*/
...
In the line marked with > I'd like to press TAB to indent the line. cc-mode simply does nothing at all if i do so. I could use spaces there (which is inconvenient) but every (semi-)automatic re-indentation of this block would cause the spaces to vanish and therefore the python code to be incorrectly indented (which is what happens if i happen to press tab somewhere on this line after indenting it with spaces).
I tried to start emacs without my .init to be sure this is default behavior and not modified by my configuration so far. I've done google searches and read the documentation of the cc-mode variables / functions I stumbled upon (cc-mode online docs) while searching for a solution (i.e. c-indent-comments-syntactically-p, c-indent-command, c-tab-always-indent,...) but none of these seemed to solve my question.
EDIT1:
Thanks to abo-abo's idea of a "multi-major-mode" setup i've stumbled upon mmm-mode and have set up automatic switching to python mode for a cog section, which fixes most of my problems.
The only remaining problem is reindenting the whole file or a region containing a cog section. Can I somehow tell cc-mode to not change anything in comments while reindenting the file? mmm-mode + that would be a perfect solution for me.
You can use M-i to force a tab indent on the lines that you want, so you can use it to indent your comments.
You can also change your comments to use // instead. Just select your python code snippet, and do M-x comment-region:
// def foo(x):
// print 'hi'
Then the autoindent won't mess up your indentation.
Someplace I saw a snippet of code which told vi to use soft tabs and set the size of a tab. If you put this snippet at the bottom of a source file, then vi would magically use those settings for that file.
What is the syntax and rules for including that snippet in a source file? Can emacs be made to use these settings as well?
You can put this in a comment in your source file:
ex: set softtabstop=4 shiftwidth=4 tabstop=4 expandtab:
The comment syntax depends on the type of the source file.
For C/C++/Java, this would be:
// ex: set softtabstop=4 shiftwidth=4 tabstop=4 expandtab:
For JSP, this would be:
<%-- ex: set softtabstop=4 shiftwidth=4 tabstop=4 expandtab: --%>
This works if it is placed at the beginning of the source file, but I'm not sure that this'll work if placed at the end of it too.
This will not work for emacs. There might be a different way of achieving the same for emacs.
Check out :h modeline.
Example:
/* vim: ai set sw=4 ts=4 */
See :h modelines for how many lines into a file Vim will check for modeline info. The default is to check the first 5 lines.
As far as I know, vi didn't have this capability. You're likely thinking of the modeline feature of Vim. There is similar functionality in emacs, where you can put local variables in the file.
Note that, at least in Vim, modelines have had a history of vulnerabilities. This is primarily due to problematic options being specifically blacklisted instead of only allowing a certain subset of variables to be set in modelines. I'd suggest using a plugin like securemodelines.
Put this in your C++ source file:
// vim: set ft=cpp
The modeline feature looks for the string "vim:" and then executes what follows. Note: this could open up potential exploits if you don't trust the files you are opening, so think twice before enabling this feature.
Okay, first of all, in real vi you do this in the .exrc file.
Second, use
set autoindent tabstop=8 shiftwidth=4
because otherwise vi will insert tabs it thinks are only 4 characters wide. The resulting text file will not look like it makes sense in any other editor.