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diff --git a/man/en/chapter_72.html b/man/en/chapter_72.html
index e0d01f50..cefa93fb 100644
--- a/man/en/chapter_72.html
+++ b/man/en/chapter_72.html
@@ -177,9 +177,9 @@
                 <div id="content" class="content">
                     <main>
                         <h3 id="janus"><a class="header" href="#janus">Janus</a></h3>
-<p><a href="https://github.com/casey/janus">Janus</a> is a tool that collects and analyzes
-<code>justfile</code>s, and can determine if a new version of <code>just</code> breaks or changes the
-interpretation of existing <code>justfile</code>s.</p>
+<p><a href="https://github.com/casey/janus">Janus</a> is a tool for checking whether a change
+to <code>just</code> breaks or changes the interpretation of existing <code>justfile</code>s. It
+collects and analyzes public <code>justfile</code>s on GitHub.</p>
 <p>Before merging a particularly large or gruesome change, Janus should be run to
 make sure that nothing breaks. Don’t worry about running Janus yourself, Casey
 will happily run it for you on changes that need it.</p>
diff --git a/man/en/print.html b/man/en/print.html
index 84ec0240..3a2783a6 100644
--- a/man/en/print.html
+++ b/man/en/print.html
@@ -2551,9 +2551,9 @@ permissive
 domain dedication and fallback license, so your changes must also be released
 under this license.</p>
 <div style="break-before: page; page-break-before: always;"></div><h3 id="janus"><a class="header" href="#janus">Janus</a></h3>
-<p><a href="https://github.com/casey/janus">Janus</a> is a tool that collects and analyzes
-<code>justfile</code>s, and can determine if a new version of <code>just</code> breaks or changes the
-interpretation of existing <code>justfile</code>s.</p>
+<p><a href="https://github.com/casey/janus">Janus</a> is a tool for checking whether a change
+to <code>just</code> breaks or changes the interpretation of existing <code>justfile</code>s. It
+collects and analyzes public <code>justfile</code>s on GitHub.</p>
 <p>Before merging a particularly large or gruesome change, Janus should be run to
 make sure that nothing breaks. Don’t worry about running Janus yourself, Casey
 will happily run it for you on changes that need it.</p>
diff --git a/man/en/searchindex.js b/man/en/searchindex.js
index 559ed75b..ce734578 100644
--- a/man/en/searchindex.js
+++ b/man/en/searchindex.js
@@ -1 +1 @@
-Object.assign(window.search, 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just is a handy way to save and run project-specific commands. This readme is also available as a book . (中文文档在 这里 , 快看过来!) Commands, called recipes, are stored in a file called justfile with syntax inspired by make: screenshot You can then run them with just RECIPE: $ just test-all\ncc *.c -o main\n./test --all\nYay, all your tests passed! just has a ton of useful features, and many improvements over make: just is a command runner, not a build system, so it avoids much of make’s complexity and idiosyncrasies . No need for .PHONY recipes! Linux, MacOS, and Windows are supported with no additional dependencies. (Although if your system doesn’t have an sh, you’ll need to choose a different shell .) Errors are specific and informative, and syntax errors are reported along with their source context. Recipes can accept command line arguments . Wherever possible, errors are resolved statically. Unknown recipes and circular dependencies are reported before anything runs. just loads .env files , making it easy to populate environment variables. Recipes can be listed from the command line . Command line completion scripts are available for most popular shells . Recipes can be written in arbitrary languages , like Python or NodeJS. just can be invoked from any subdirectory, not just the directory that contains the justfile. And much more ! If you need help with just please feel free to open an issue or ping me on Discord . Feature requests and bug reports are always welcome!","breadcrumbs":"Introduction","id":"0","title":"Introduction"},"1":{"body":"","breadcrumbs":"Introduction » Installation » Installation","id":"1","title":"Installation"},"10":{"body":"vim-just The vim-just plugin provides syntax highlighting for justfiles. Install it with your favorite package manager, like Plug : call plug#begin() Plug 'NoahTheDuke/vim-just' call plug#end() Or with Vim’s built-in package support: mkdir -p ~/.vim/pack/vendor/start\ncd ~/.vim/pack/vendor/start\ngit clone https://github.com/NoahTheDuke/vim-just.git tree-sitter-just tree-sitter-just is an Nvim Treesitter plugin for Neovim. Makefile Syntax Highlighting Vim’s built-in makefile syntax highlighting isn’t perfect for justfiles, but it’s better than nothing. You can put the following in ~/.vim/filetype.vim: if exists(\"did_load_filetypes\") finish\nendif augroup filetypedetect au BufNewFile,BufRead justfile setf make\naugroup END Or add the following to an individual justfile to enable make mode on a per-file basis: # vim: set ft=make :","breadcrumbs":"Introduction » Editor Support » Vim and Neovim » Vim and Neovim","id":"10","title":"Vim and Neovim"},"11":{"body":"just-mode provides syntax highlighting and automatic indentation of justfiles. It is available on MELPA as just-mode . justl provides commands for executing and listing recipes. You can add the following to an individual justfile to enable make mode on a per-file basis: # Local Variables:\n# mode: makefile\n# End:","breadcrumbs":"Introduction » Editor Support » Emacs » Emacs","id":"11","title":"Emacs"},"12":{"body":"An extension for VS Code by skellock is available here ( repository ), but is no longer actively developed. You can install it from the command line by running: code --install-extension skellock.just An more recently active fork by sclu1034 is available here .","breadcrumbs":"Introduction » Editor Support » Visual Studio Code » Visual Studio Code","id":"12","title":"Visual Studio Code"},"13":{"body":"A plugin for JetBrains IDEs by linux_china is available here .","breadcrumbs":"Introduction » Editor Support » JetBrains IDEs » JetBrains IDEs","id":"13","title":"JetBrains IDEs"},"14":{"body":"Kakoune supports justfile syntax highlighting out of the box, thanks to TeddyDD.","breadcrumbs":"Introduction » Editor Support » Kakoune » Kakoune","id":"14","title":"Kakoune"},"15":{"body":"Helix supports justfile syntax highlighting out-of-the-box since version 23.05.","breadcrumbs":"Introduction » Editor Support » Helix » Helix","id":"15","title":"Helix"},"16":{"body":"The Just package by nk9 with just syntax and some other tools is available on PackageControl .","breadcrumbs":"Introduction » Editor Support » Sublime Text » Sublime Text","id":"16","title":"Sublime Text"},"17":{"body":"Micro supports Justfile syntax highlighting out of the box, thanks to tomodachi94 .","breadcrumbs":"Introduction » Editor Support » Micro » Micro","id":"17","title":"Micro"},"18":{"body":"Feel free to send me the commands necessary to get syntax highlighting working in your editor of choice so that I may include them here.","breadcrumbs":"Introduction » Editor Support » Other Editors » Other Editors","id":"18","title":"Other Editors"},"19":{"body":"See the installation section for how to install just on your computer. Try running just --version to make sure that it’s installed correctly. For an overview of the syntax, check out this cheatsheet . Once just is installed and working, create a file named justfile in the root of your project with the following contents: recipe-name: echo 'This is a recipe!' # this is a comment\nanother-recipe: @echo 'This is another recipe.' When you invoke just it looks for file justfile in the current directory and upwards, so you can invoke it from any subdirectory of your project. The search for a justfile is case insensitive, so any case, like Justfile, JUSTFILE, or JuStFiLe, will work. just will also look for files with the name .justfile, in case you’d like to hide a justfile. Running just with no arguments runs the first recipe in the justfile: $ just\necho 'This is a recipe!'\nThis is a recipe! One or more arguments specify the recipe(s) to run: $ just another-recipe\nThis is another recipe. just prints each command to standard error before running it, which is why echo 'This is a recipe!' was printed. This is suppressed for lines starting with @, which is why echo 'This is another recipe.' was not printed. Recipes stop running if a command fails. Here cargo publish will only run if cargo test succeeds: publish: cargo test # tests passed, time to publish! cargo publish Recipes can depend on other recipes. Here the test recipe depends on the build recipe, so build will run before test: build: cc main.c foo.c bar.c -o main test: build ./test sloc: @echo \"`wc -l *.c` lines of code\" $ just test\ncc main.c foo.c bar.c -o main\n./test\ntesting… all tests passed! Recipes without dependencies will run in the order they’re given on the command line: $ just build sloc\ncc main.c foo.c bar.c -o main\n1337 lines of code Dependencies will always run first, even if they are passed after a recipe that depends on them: $ just test build\ncc main.c foo.c bar.c -o main\n./test\ntesting… all tests passed!","breadcrumbs":"Introduction » Quick Start » Quick Start","id":"19","title":"Quick Start"},"2":{"body":"just should run on any system with a reasonable sh, including Linux, MacOS, and the BSDs. On Windows, just works with the sh provided by Git for Windows , GitHub Desktop , or Cygwin . If you’d rather not install sh, you can use the shell setting to use the shell of your choice. Like PowerShell: # use PowerShell instead of sh:\nset shell := [\"powershell.exe\", \"-c\"] hello: Write-Host \"Hello, world!\" …or cmd.exe: # use cmd.exe instead of sh:\nset shell := [\"cmd.exe\", \"/c\"] list: dir You can also set the shell using command-line arguments. For example, to use PowerShell, launch just with --shell powershell.exe --shell-arg -c. (PowerShell is installed by default on Windows 7 SP1 and Windows Server 2008 R2 S1 and later, and cmd.exe is quite fiddly, so PowerShell is recommended for most Windows users.)","breadcrumbs":"Introduction » Installation » Prerequisites » Prerequisites","id":"2","title":"Prerequisites"},"20":{"body":"A variety of example justfiles can be found in the examples directory .","breadcrumbs":"Introduction » Examples » Examples","id":"20","title":"Examples"},"21":{"body":"","breadcrumbs":"Introduction » Features » Features","id":"21","title":"Features"},"22":{"body":"When just is invoked without a recipe, it runs the first recipe in the justfile. This recipe might be the most frequently run command in the project, like running the tests: test: cargo test You can also use dependencies to run multiple recipes by default: default: lint build test build: echo Building… test: echo Testing… lint: echo Linting… If no recipe makes sense as the default recipe, you can add a recipe to the beginning of your justfile that lists the available recipes: default: just --list","breadcrumbs":"Introduction » Features » The Default Recipe » The Default Recipe","id":"22","title":"The Default Recipe"},"23":{"body":"Recipes can be listed in alphabetical order with just --list: $ just --list\nAvailable recipes: build test deploy lint just --summary is more concise: $ just --summary\nbuild test deploy lint Pass --unsorted to print recipes in the order they appear in the justfile: test: echo 'Testing!' build: echo 'Building!' $ just --list --unsorted\nAvailable recipes: test build $ just --summary --unsorted\ntest build If you’d like just to default to listing the recipes in the justfile, you can use this as your default recipe: default: @just --list Note that you may need to add --justfile {{justfile()}} to the line above. Without it, if you executed just -f /some/distant/justfile -d . or just -f ./non-standard-justfile, the plain just --list inside the recipe would not necessarily use the file you provided. It would try to find a justfile in your current path, maybe even resulting in a No justfile found error. The heading text can be customized with --list-heading: $ just --list --list-heading $'Cool stuff…\\n'\nCool stuff… test build And the indentation can be customized with --list-prefix: $ just --list --list-prefix ····\nAvailable recipes:\n····test\n····build The argument to --list-heading replaces both the heading and the newline following it, so it should contain a newline if non-empty. It works this way so you can suppress the heading line entirely by passing the empty string: $ just --list --list-heading '' test build","breadcrumbs":"Introduction » Features » Listing Available Recipes » Listing Available Recipes","id":"23","title":"Listing Available Recipes"},"24":{"body":"Aliases allow recipes to be invoked on the command line with alternative names: alias b := build build: echo 'Building!' $ just b\necho 'Building!'\nBuilding!","breadcrumbs":"Introduction » Features » Aliases » Aliases","id":"24","title":"Aliases"},"25":{"body":"Settings control interpretation and execution. Each setting may be specified at most once, anywhere in the justfile. For example: set shell := [\"zsh\", \"-cu\"] foo: # this line will be run as `zsh -cu 'ls **/*.txt'` ls **/*.txt Table of Settings Name Value Default Description allow-duplicate-recipes boolean false Allow recipes appearing later in a justfile to override earlier recipes with the same name. dotenv-filename string - Load a .env file with a custom name, if present. dotenv-load boolean false Load a .env file, if present. dotenv-path string - Load a .env file from a custom path, if present. Overrides dotenv-filename. export boolean false Export all variables as environment variables. fallback boolean false Search justfile in parent directory if the first recipe on the command line is not found. ignore-comments boolean false Ignore recipe lines beginning with #. positional-arguments boolean false Pass positional arguments. shell [COMMAND, ARGS…] - Set the command used to invoke recipes and evaluate backticks. tempdir string - Create temporary directories in tempdir instead of the system default temporary directory. windows-powershell boolean false Use PowerShell on Windows as default shell. (Deprecated. Use windows-shell instead. windows-shell [COMMAND, ARGS…] - Set the command used to invoke recipes and evaluate backticks. Boolean settings can be written as: set NAME Which is equivalent to: set NAME := true Allow Duplicate Recipes If allow-duplicate-recipes is set to true, defining multiple recipes with the same name is not an error and the last definition is used. Defaults to false. set allow-duplicate-recipes @foo: echo foo @foo: echo bar $ just foo\nbar Dotenv Settings If dotenv-load, dotenv-filename or dotenv-path is set, just will load environment variables from a file. If dotenv-path is set, just will look for a file at the given path. Otherwise, just looks for a file named .env by default, unless dotenv-filename set, in which case the value of dotenv-filename is used. This file can be located in the same directory as your justfile or in a parent directory. The loaded variables are environment variables, not just variables, and so must be accessed using $VARIABLE_NAME in recipes and backticks. For example, if your .env file contains: # a comment, will be ignored\nDATABASE_ADDRESS=localhost:6379\nSERVER_PORT=1337 And your justfile contains: set dotenv-load serve: @echo \"Starting server with database $DATABASE_ADDRESS on port $SERVER_PORT…\" ./server --database $DATABASE_ADDRESS --port $SERVER_PORT just serve will output: $ just serve\nStarting server with database localhost:6379 on port 1337…\n./server --database $DATABASE_ADDRESS --port $SERVER_PORT Export The export setting causes all just variables to be exported as environment variables. Defaults to false. set export a := \"hello\" @foo b: echo $a echo $b $ just foo goodbye\nhello\ngoodbye Positional Arguments If positional-arguments is true, recipe arguments will be passed as positional arguments to commands. For linewise recipes, argument $0 will be the name of the recipe. For example, running this recipe: set positional-arguments @foo bar: echo $0 echo $1 Will produce the following output: $ just foo hello\nfoo\nhello When using an sh-compatible shell, such as bash or zsh, $@ expands to the positional arguments given to the recipe, starting from one. When used within double quotes as \"$@\", arguments including whitespace will be passed on as if they were double-quoted. That is, \"$@\" is equivalent to \"$1\" \"$2\"… When there are no positional parameters, \"$@\" and $@ expand to nothing (i.e., they are removed). This example recipe will print arguments one by one on separate lines: set positional-arguments @test *args='': bash -c 'while (( \"$#\" )); do echo - $1; shift; done' -- \"$@\" Running it with two arguments: $ just test foo \"bar baz\"\n- foo\n- bar baz Shell The shell setting controls the command used to invoke recipe lines and backticks. Shebang recipes are unaffected. # use python3 to execute recipe lines and backticks\nset shell := [\"python3\", \"-c\"] # use print to capture result of evaluation\nfoos := `print(\"foo\" * 4)` foo: print(\"Snake snake snake snake.\") print(\"{{foos}}\") just passes the command to be executed as an argument. Many shells will need an additional flag, often -c, to make them evaluate the first argument. Windows Shell just uses sh on Windows by default. To use a different shell on Windows, use windows-shell: set windows-shell := [\"powershell.exe\", \"-NoLogo\", \"-Command\"] hello: Write-Host \"Hello, world!\" See powershell.just for a justfile that uses PowerShell on all platforms. Windows PowerShell set windows-powershell uses the legacy powershell.exe binary, and is no longer recommended. See the windows-shell setting above for a more flexible way to control which shell is used on Windows. just uses sh on Windows by default. To use powershell.exe instead, set windows-powershell to true. set windows-powershell := true hello: Write-Host \"Hello, world!\" Python 3 set shell := [\"python3\", \"-c\"] Bash set shell := [\"bash\", \"-uc\"] Z Shell set shell := [\"zsh\", \"-uc\"] Fish set shell := [\"fish\", \"-c\"] Nushell set shell := [\"nu\", \"-c\"] If you want to change the default table mode to light: set shell := ['nu', '-m', 'light', '-c'] Nushell was written in Rust, and has cross-platform support for Windows / macOS and Linux .","breadcrumbs":"Introduction » Features » Settings » Settings","id":"25","title":"Settings"},"26":{"body":"Comments immediately preceding a recipe will appear in just --list: # build stuff\nbuild: ./bin/build # test stuff\ntest: ./bin/test $ just --list\nAvailable recipes: build # build stuff test # test stuff","breadcrumbs":"Introduction » Features » Documentation Comments » Documentation Comments","id":"26","title":"Documentation Comments"},"27":{"body":"Variables, strings, concatenation, path joining, and substitution using {{…}} are supported: tmpdir := `mktemp -d`\nversion := \"0.2.7\"\ntardir := tmpdir / \"awesomesauce-\" + version\ntarball := tardir + \".tar.gz\" publish: rm -f {{tarball}} mkdir {{tardir}} cp README.md *.c {{tardir}} tar zcvf {{tarball}} {{tardir}} scp {{tarball}} me@server.com:release/ rm -rf {{tarball}} {{tardir}} Joining Paths The / operator can be used to join two strings with a slash: foo := \"a\" / \"b\" $ just --evaluate foo\na/b Note that a / is added even if one is already present: foo := \"a/\"\nbar := foo / \"b\" $ just --evaluate bar\na//b Absolute paths can also be constructed1.5.0: foo := / \"b\" $ just --evaluate foo\n/b The / operator uses the / character, even on Windows. Thus, using the / operator should be avoided with paths that use universal naming convention (UNC), i.e., those that start with \\?, since forward slashes are not supported with UNC paths. Escaping {{ To write a recipe containing {{, use {{{{: braces: echo 'I {{{{LOVE}} curly braces!' (An unmatched }} is ignored, so it doesn’t need to be escaped.) Another option is to put all the text you’d like to escape inside of an interpolation: braces: echo '{{'I {{LOVE}} curly braces!'}}' Yet another option is to use {{ \"{{\" }}: braces: echo 'I {{ \"{{\" }}LOVE}} curly braces!'","breadcrumbs":"Introduction » Features » Variables and Substitution » Variables and Substitution","id":"27","title":"Variables and Substitution"},"28":{"body":"Double-quoted strings support escape sequences: string-with-tab := \"\\t\"\nstring-with-newline := \"\\n\"\nstring-with-carriage-return := \"\\r\"\nstring-with-double-quote := \"\\\"\"\nstring-with-slash := \"\\\\\"\nstring-with-no-newline := \"\\\n\" $ just --evaluate\n\"tring-with-carriage-return := \"\nstring-with-double-quote := \"\"\"\nstring-with-newline := \"\n\"\nstring-with-no-newline := \"\"\nstring-with-slash := \"\\\"\nstring-with-tab := \" \" Strings may contain line breaks: single := '\nhello\n' double := \"\ngoodbye\n\" Single-quoted strings do not recognize escape sequences: escapes := '\\t\\n\\r\\\"\\\\' $ just --evaluate\nescapes := \"\\t\\n\\r\\\"\\\\\" Indented versions of both single- and double-quoted strings, delimited by triple single- or triple double-quotes, are supported. Indented string lines are stripped of a leading line break, and leading whitespace common to all non-blank lines: # this string will evaluate to `foo\\nbar\\n`\nx := ''' foo bar\n''' # this string will evaluate to `abc\\n wuv\\nxyz\\n`\ny := \"\"\" abc wuv xyz\n\"\"\" Similar to unindented strings, indented double-quoted strings process escape sequences, and indented single-quoted strings ignore escape sequences. Escape sequence processing takes place after unindentation. The unindentation algorithm does not take escape-sequence produced whitespace or newlines into account.","breadcrumbs":"Introduction » Features » Strings » Strings","id":"28","title":"Strings"},"29":{"body":"Normally, if a command returns a non-zero exit status, execution will stop. To continue execution after a command, even if it fails, prefix the command with -: foo: -cat foo echo 'Done!' $ just foo\ncat foo\ncat: foo: No such file or directory\necho 'Done!'\nDone!","breadcrumbs":"Introduction » Features » Ignoring Errors » Ignoring Errors","id":"29","title":"Ignoring Errors"},"3":{"body":"Operating System Package Manager Package Command Alpine Linux apk-tools just apk add just Arch Linux pacman just pacman -S just Debian and Ubuntu derivatives MPR just git clone https://mpr.makedeb.org/just cd just makedeb -si Debian and Ubuntu derivatives Prebuilt-MPR just You must have the Prebuilt-MPR set up on your system in order to run this command. sudo apt install just Fedora Linux DNF just dnf install just FreeBSD pkg just pkg install just Gentoo Linux Portage guru/dev-build/just eselect repository enable guru emerge --sync guru emerge dev-build/just macOS MacPorts just port install just Microsoft Windows Chocolatey just choco install just Microsoft Windows Scoop just scoop install just Microsoft Windows Windows Package Manager Casey/Just winget install --id Casey.Just --exact NixOS Nix just nix-env -iA nixos.just openSUSE Zypper just zypper in just Solus eopkg just eopkg install just Various asdf just asdf plugin add just asdf install just &lt;version&gt; Various Cargo just cargo install just Various Conda just conda install -c conda-forge just Various Homebrew just brew install just Various Nix just nix-env -iA nixpkgs.just Various Snap just snap install --edge --classic just Void Linux XBPS just xbps-install -S just package version table","breadcrumbs":"Introduction » Installation » Packages » Packages","id":"3","title":"Packages"},"30":{"body":"just provides a few built-in functions that might be useful when writing recipes. System Information arch() — Instruction set architecture. Possible values are: \"aarch64\", \"arm\", \"asmjs\", \"hexagon\", \"mips\", \"msp430\", \"powerpc\", \"powerpc64\", \"s390x\", \"sparc\", \"wasm32\", \"x86\", \"x86_64\", and \"xcore\". num_cpus()1.15.0 - Number of logical CPUs. os() — Operating system. Possible values are: \"android\", \"bitrig\", \"dragonfly\", \"emscripten\", \"freebsd\", \"haiku\", \"ios\", \"linux\", \"macos\", \"netbsd\", \"openbsd\", \"solaris\", and \"windows\". os_family() — Operating system family; possible values are: \"unix\" and \"windows\". For example: system-info: @echo \"This is an {{arch()}} machine\". $ just system-info\nThis is an x86_64 machine The os_family() function can be used to create cross-platform justfiles that work on various operating systems. For an example, see cross-platform.just file. Environment Variables env_var(key) — Retrieves the environment variable with name key, aborting if it is not present. home_dir := env_var('HOME') test: echo \"{{home_dir}}\" $ just\n/home/user1 env_var_or_default(key, default) — Retrieves the environment variable with name key, returning default if it is not present. env(key)1.15.0 — Alias for env_var(key). env(key, default)1.15.0 — Alias for env_var_or_default(key, default). Invocation Directory invocation_directory() - Retrieves the absolute path to the current directory when just was invoked, before just changed it (chdir’d) prior to executing commands. On Windows, invocation_directory() uses cygpath to convert the invocation directory to a Cygwin-compatible /-separated path. Use invocation_directory_native() to return the verbatim invocation directory on all platforms. For example, to call rustfmt on files just under the “current directory” (from the user/invoker’s perspective), use the following rule: rustfmt: find {{invocation_directory()}} -name \\*.rs -exec rustfmt {} \\; Alternatively, if your command needs to be run from the current directory, you could use (e.g.): build: cd {{invocation_directory()}}; ./some_script_that_needs_to_be_run_from_here invocation_directory_native() - Retrieves the absolute path to the current directory when just was invoked, before just changed it (chdir’d) prior to executing commands. Justfile and Justfile Directory justfile() - Retrieves the path of the current justfile. justfile_directory() - Retrieves the path of the parent directory of the current justfile. For example, to run a command relative to the location of the current justfile: script: ./{{justfile_directory()}}/scripts/some_script Just Executable just_executable() - Absolute path to the just executable. For example: executable: @echo The executable is at: {{just_executable()}} $ just\nThe executable is at: /bin/just Just Process ID just_pid() - Process ID of the just executable. For example: pid: @echo The process ID is: {{ just_pid() }} $ just\nThe process ID is: 420 String Manipulation quote(s) - Replace all single quotes with '\\'' and prepend and append single quotes to s. This is sufficient to escape special characters for many shells, including most Bourne shell descendants. replace(s, from, to) - Replace all occurrences of from in s to to. replace_regex(s, regex, replacement) - Replace all occurrences of regex in s to replacement. Regular expressions are provided by the Rust regex crate . See the syntax documentation for usage examples. Capture groups are supported. The replacement string uses Replacement string syntax . trim(s) - Remove leading and trailing whitespace from s. trim_end(s) - Remove trailing whitespace from s. trim_end_match(s, pat) - Remove suffix of s matching pat. trim_end_matches(s, pat) - Repeatedly remove suffixes of s matching pat. trim_start(s) - Remove leading whitespace from s. trim_start_match(s, pat) - Remove prefix of s matching pat. trim_start_matches(s, pat) - Repeatedly remove prefixes of s matching pat. Case Conversion capitalize(s)1.7.0 - Convert first character of s to uppercase and the rest to lowercase. kebabcase(s)1.7.0 - Convert s to kebab-case. lowercamelcase(s)1.7.0 - Convert s to lowerCamelCase. lowercase(s) - Convert s to lowercase. shoutykebabcase(s)1.7.0 - Convert s to SHOUTY-KEBAB-CASE. shoutysnakecase(s)1.7.0 - Convert s to SHOUTY_SNAKE_CASE. snakecase(s)1.7.0 - Convert s to snake_case. titlecase(s)1.7.0 - Convert s to Title Case. uppercamelcase(s)1.7.0 - Convert s to UpperCamelCase. uppercase(s) - Convert s to uppercase. Path Manipulation Fallible absolute_path(path) - Absolute path to relative path in the working directory. absolute_path(\"./bar.txt\") in directory /foo is /foo/bar.txt. canonicalize(path)1.24.0 - Canonicalize path by resolving symlinks and removing ., .., and extra /s where possible. extension(path) - Extension of path. extension(\"/foo/bar.txt\") is txt. file_name(path) - File name of path with any leading directory components removed. file_name(\"/foo/bar.txt\") is bar.txt. file_stem(path) - File name of path without extension. file_stem(\"/foo/bar.txt\") is bar. parent_directory(path) - Parent directory of path. parent_directory(\"/foo/bar.txt\") is /foo. without_extension(path) - path without extension. without_extension(\"/foo/bar.txt\") is /foo/bar. These functions can fail, for example if a path does not have an extension, which will halt execution. Infallible clean(path) - Simplify path by removing extra path separators, intermediate . components, and .. where possible. clean(\"foo//bar\") is foo/bar, clean(\"foo/..\") is ., clean(\"foo/./bar\") is foo/bar. join(a, b…) - This function uses / on Unix and \\ on Windows, which can be lead to unwanted behavior. The / operator, e.g., a / b, which always uses /, should be considered as a replacement unless \\s are specifically desired on Windows. Join path a with path b. join(\"foo/bar\", \"baz\") is foo/bar/baz. Accepts two or more arguments. Filesystem Access path_exists(path) - Returns true if the path points at an existing entity and false otherwise. Traverses symbolic links, and returns false if the path is inaccessible or points to a broken symlink. Error Reporting error(message) - Abort execution and report error message to user. UUID and Hash Generation blake3(string)1.25.0 - Return BLAKE3 hash of string as hexadecimal string. blake3_file(path)1.25.0 - Return BLAKE3 hash of file at path as hexadecimal string. sha256(string) - Return the SHA-256 hash of string as hexadecimal string. sha256_file(path) - Return SHA-256 hash of file at path as hexadecimal string. uuid() - Generate a random version 4 UUID. Semantic Versions semver_matches(version, requirement)1.16.0 - Check whether a semantic version , e.g., \"0.1.0\" matches a requirement, e.g., \">=0.1.0\", returning \"true\" if so and \"false\" otherwise. XDG Directories1.23.0 These functions return paths to user-specific directories for things like configuration, data, caches, executables, and the user’s home directory. These functions follow the XDG Base Directory Specification , and are implemented with the dirs crate. cache_directory() - The user-specific cache directory. config_directory() - The user-specific configuration directory. config_local_directory() - The local user-specific configuration directory. data_directory() - The user-specific data directory. data_local_directory() - The local user-specific data directory. executable_directory() - The user-specific executable directory. home_directory() - The user’s home directory.","breadcrumbs":"Introduction » Features » Functions » Functions","id":"30","title":"Functions"},"31":{"body":"Recipes may be annotated with attributes that change their behavior. Name Description [confirm]1.17.0 Require confirmation prior to executing recipe. [confirm(\"prompt\")]1.23.0 Require confirmation prior to executing recipe with a custom prompt. [linux]1.8.0 Enable recipe on Linux. [macos]1.8.0 Enable recipe on MacOS. [no-cd]1.9.0 Don’t change directory before executing recipe. [no-exit-message]1.7.0 Don’t print an error message if recipe fails. [no-quiet]1.23.0 Override globally quiet recipes and always echo out the recipe. [private]1.10.0 See Private Recipes . [unix]1.8.0 Enable recipe on Unixes. (Includes MacOS). [windows]1.8.0 Enable recipe on Windows. A recipe can have multiple attributes, either on multiple lines: [no-cd]\n[private]\nfoo: echo \"foo\" Or separated by commas on a single line1.14.0: [no-cd, private]\nfoo: echo \"foo\" Enabling and Disabling Recipes1.8.0 The [linux], [macos], [unix], and [windows] attributes are configuration attributes. By default, recipes are always enabled. A recipe with one or more configuration attributes will only be enabled when one or more of those configurations is active. This can be used to write justfiles that behave differently depending on which operating system they run on. The run recipe in this justfile will compile and run main.c, using a different C compiler and using the correct output binary name for that compiler depending on the operating system: [unix]\nrun: cc main.c ./a.out [windows]\nrun: cl main.c main.exe Disabling Changing Directory1.9.0 just normally executes recipes with the current directory set to the directory that contains the justfile. This can be disabled using the [no-cd] attribute. This can be used to create recipes which use paths relative to the invocation directory, or which operate on the current directory. For example, this commit recipe: [no-cd]\ncommit file: git add {{file}} git commit Can be used with paths that are relative to the current directory, because [no-cd] prevents just from changing the current directory when executing commit. Requiring Confirmation for Recipes1.17.0 just normally executes all recipes unless there is an error. The [confirm] attribute allows recipes require confirmation in the terminal prior to running. This can be overridden by passing --yes to just, which will automatically confirm any recipes marked by this attribute. Recipes dependent on a recipe that requires confirmation will not be run if the relied upon recipe is not confirmed, as well as recipes passed after any recipe that requires confirmation. [confirm]\ndelete-all: rm -rf * Custom Confirmation Prompt1.23.0 The default confirmation prompt can be overridden with [confirm(PROMPT)]: [confirm(\"Are you sure you want to delete everything?\")]\ndelete-everything: rm -rf *","breadcrumbs":"Introduction » Features » Recipe Attributes » Recipe Attributes","id":"31","title":"Recipe Attributes"},"32":{"body":"Backticks can be used to store the result of commands: localhost := `dumpinterfaces | cut -d: -f2 | sed 's/\\/.*//' | sed 's/ //g'` serve: ./serve {{localhost}} 8080 Indented backticks, delimited by three backticks, are de-indented in the same manner as indented strings: # This backtick evaluates the command `echo foo\\necho bar\\n`, which produces the value `foo\\nbar\\n`.\nstuff := ``` echo foo echo bar ``` See the Strings section for details on unindenting. Backticks may not start with #!. This syntax is reserved for a future upgrade.","breadcrumbs":"Introduction » Features » Command Evaluation Using Backticks » Command Evaluation Using Backticks","id":"32","title":"Command Evaluation Using Backticks"},"33":{"body":"if/else expressions evaluate different branches depending on if two expressions evaluate to the same value: foo := if \"2\" == \"2\" { \"Good!\" } else { \"1984\" } bar: @echo \"{{foo}}\" $ just bar\nGood! It is also possible to test for inequality: foo := if \"hello\" != \"goodbye\" { \"xyz\" } else { \"abc\" } bar: @echo {{foo}} $ just bar\nxyz And match against regular expressions: foo := if \"hello\" =~ 'hel+o' { \"match\" } else { \"mismatch\" } bar: @echo {{foo}} $ just bar\nmatch Regular expressions are provided by the regex crate , whose syntax is documented on docs.rs . Since regular expressions commonly use backslash escape sequences, consider using single-quoted string literals, which will pass slashes to the regex parser unmolested. Conditional expressions short-circuit, which means they only evaluate one of their branches. This can be used to make sure that backtick expressions don’t run when they shouldn’t. foo := if env_var(\"RELEASE\") == \"true\" { `get-something-from-release-database` } else { \"dummy-value\" } Conditionals can be used inside of recipes: bar foo: echo {{ if foo == \"bar\" { \"hello\" } else { \"goodbye\" } }} Note the space after the final }! Without the space, the interpolation will be prematurely closed. Multiple conditionals can be chained: foo := if \"hello\" == \"goodbye\" { \"xyz\"\n} else if \"a\" == \"a\" { \"abc\"\n} else { \"123\"\n} bar: @echo {{foo}} $ just bar\nabc","breadcrumbs":"Introduction » Features » Conditional Expressions » Conditional Expressions","id":"33","title":"Conditional Expressions"},"34":{"body":"Execution can be halted with the error function. For example: foo := if \"hello\" == \"goodbye\" { \"xyz\"\n} else if \"a\" == \"b\" { \"abc\"\n} else { error(\"123\")\n} Which produce the following error when run: error: Call to function `error` failed: 123 |\n16 | error(\"123\")","breadcrumbs":"Introduction » Features » Stopping execution with error » Stopping execution with error","id":"34","title":"Stopping execution with error"},"35":{"body":"Variables can be overridden from the command line. os := \"linux\" test: build ./test --test {{os}} build: ./build {{os}} $ just\n./build linux\n./test --test linux Any number of arguments of the form NAME=VALUE can be passed before recipes: $ just os=plan9\n./build plan9\n./test --test plan9 Or you can use the --set flag: $ just --set os bsd\n./build bsd\n./test --test bsd","breadcrumbs":"Introduction » Features » Setting Variables from the Command Line » Setting Variables from the Command Line","id":"35","title":"Setting Variables from the Command Line"},"36":{"body":"Exporting just Variables Assignments prefixed with the export keyword will be exported to recipes as environment variables: export RUST_BACKTRACE := \"1\" test: # will print a stack trace if it crashes cargo test Parameters prefixed with a $ will be exported as environment variables: test $RUST_BACKTRACE=\"1\": # will print a stack trace if it crashes cargo test Exported variables and parameters are not exported to backticks in the same scope. export WORLD := \"world\"\n# This backtick will fail with \"WORLD: unbound variable\"\nBAR := `echo hello $WORLD` # Running `just a foo` will fail with \"A: unbound variable\"\na $A $B=`echo $A`: echo $A $B When export is set, all just variables are exported as environment variables. Getting Environment Variables from the environment Environment variables from the environment are passed automatically to the recipes. print_home_folder: echo \"HOME is: '${HOME}'\" $ just\nHOME is '/home/myuser' Setting just Variables from Environment Variables Environment variables can be propagated to just variables using the functions env_var() and env_var_or_default(). See environment-variables .","breadcrumbs":"Introduction » Features » Getting and Setting Environment Variables » Getting and Setting Environment Variables","id":"36","title":"Getting and Setting Environment Variables"},"37":{"body":"Recipes may have parameters. Here recipe build has a parameter called target: build target: @echo 'Building {{target}}…' cd {{target}} && make To pass arguments on the command line, put them after the recipe name: $ just build my-awesome-project\nBuilding my-awesome-project…\ncd my-awesome-project && make To pass arguments to a dependency, put the dependency in parentheses along with the arguments: default: (build \"main\") build target: @echo 'Building {{target}}…' cd {{target}} && make Variables can also be passed as arguments to dependencies: target := \"main\" _build version: @echo 'Building {{version}}…' cd {{version}} && make build: (_build target) A command’s arguments can be passed to dependency by putting the dependency in parentheses along with the arguments: build target: @echo \"Building {{target}}…\" push target: (build target) @echo 'Pushing {{target}}…' Parameters may have default values: default := 'all' test target tests=default: @echo 'Testing {{target}}:{{tests}}…' ./test --tests {{tests}} {{target}} Parameters with default values may be omitted: $ just test server\nTesting server:all…\n./test --tests all server Or supplied: $ just test server unit\nTesting server:unit…\n./test --tests unit server Default values may be arbitrary expressions, but concatenations or path joins must be parenthesized: arch := \"wasm\" test triple=(arch + \"-unknown-unknown\") input=(arch / \"input.dat\"): ./test {{triple}} The last parameter of a recipe may be variadic, indicated with either a + or a * before the argument name: backup +FILES: scp {{FILES}} me@server.com: Variadic parameters prefixed with + accept one or more arguments and expand to a string containing those arguments separated by spaces: $ just backup FAQ.md GRAMMAR.md\nscp FAQ.md GRAMMAR.md me@server.com:\nFAQ.md 100% 1831 1.8KB/s 00:00\nGRAMMAR.md 100% 1666 1.6KB/s 00:00 Variadic parameters prefixed with * accept zero or more arguments and expand to a string containing those arguments separated by spaces, or an empty string if no arguments are present: commit MESSAGE *FLAGS: git commit {{FLAGS}} -m \"{{MESSAGE}}\" Variadic parameters can be assigned default values. These are overridden by arguments passed on the command line: test +FLAGS='-q': cargo test {{FLAGS}} {{…}} substitutions may need to be quoted if they contain spaces. For example, if you have the following recipe: search QUERY: lynx https://www.google.com/?q={{QUERY}} And you type: $ just search \"cat toupee\" just will run the command lynx https://www.google.com/?q=cat toupee, which will get parsed by sh as lynx, https://www.google.com/?q=cat, and toupee, and not the intended lynx and https://www.google.com/?q=cat toupee. You can fix this by adding quotes: search QUERY: lynx 'https://www.google.com/?q={{QUERY}}' Parameters prefixed with a $ will be exported as environment variables: foo $bar: echo $bar","breadcrumbs":"Introduction » Features » Recipe Parameters » Recipe Parameters","id":"37","title":"Recipe Parameters"},"38":{"body":"Normal dependencies of a recipes always run before a recipe starts. That is to say, the dependee always runs before the depender. These dependencies are called “prior dependencies”. A recipe can also have subsequent dependencies, which run after the recipe and are introduced with an &&: a: echo 'A!' b: a && c d echo 'B!' c: echo 'C!' d: echo 'D!' …running b prints: $ just b\necho 'A!'\nA!\necho 'B!'\nB!\necho 'C!'\nC!\necho 'D!'\nD!","breadcrumbs":"Introduction » Features » Running Recipes at the End of a Recipe » Running Recipes at the End of a Recipe","id":"38","title":"Running Recipes at the End of a Recipe"},"39":{"body":"just doesn’t support running recipes in the middle of another recipe, but you can call just recursively in the middle of a recipe. Given the following justfile: a: echo 'A!' b: a echo 'B start!' just c echo 'B end!' c: echo 'C!' …running b prints: $ just b\necho 'A!'\nA!\necho 'B start!'\nB start!\necho 'C!'\nC!\necho 'B end!'\nB end! This has limitations, since recipe c is run with an entirely new invocation of just: Assignments will be recalculated, dependencies might run twice, and command line arguments will not be propagated to the child just process.","breadcrumbs":"Introduction » Features » Running Recipes in the Middle of a Recipe » Running Recipes in the Middle of a Recipe","id":"39","title":"Running Recipes in the Middle of a Recipe"},"4":{"body":"Pre-built binaries for Linux, MacOS, and Windows can be found on the releases page . You can use the following command on Linux, MacOS, or Windows to download the latest release, just replace DEST with the directory where you’d like to put just: curl --proto '=https' --tlsv1.2 -sSf https://just.systems/install.sh | bash -s -- --to DEST For example, to install just to ~/bin: # create ~/bin\nmkdir -p ~/bin # download and extract just to ~/bin/just\ncurl --proto '=https' --tlsv1.2 -sSf https://just.systems/install.sh | bash -s -- --to ~/bin # add `~/bin` to the paths that your shell searches for executables\n# this line should be added to your shells initialization file,\n# e.g. `~/.bashrc` or `~/.zshrc`\nexport PATH=\"$PATH:$HOME/bin\" # just should now be executable\njust --help Note that install.sh may fail on GitHub Actions, or in other environments where many machines share IP addresses. install.sh calls GitHub APIs in order to determine the latest version of just to install, and those API calls are rate-limited on a per-IP basis. To make install.sh more reliable in such circumstances, pass a specific tag to install with --tag.","breadcrumbs":"Introduction » Installation » Pre-Built Binaries » Pre-Built Binaries","id":"4","title":"Pre-Built Binaries"},"40":{"body":"Recipes that start with #! are called shebang recipes, and are executed by saving the recipe body to a file and running it. This lets you write recipes in different languages: polyglot: python js perl sh ruby nu python: #!/usr/bin/env python3 print('Hello from python!') js: #!/usr/bin/env node console.log('Greetings from JavaScript!') perl: #!/usr/bin/env perl print \"Larry Wall says Hi!\\n\"; sh: #!/usr/bin/env sh hello='Yo' echo \"$hello from a shell script!\" nu: #!/usr/bin/env nu let hello = 'Hola' echo $\"($hello) from a nushell script!\" ruby: #!/usr/bin/env ruby puts \"Hello from ruby!\" $ just polyglot\nHello from python!\nGreetings from JavaScript!\nLarry Wall says Hi!\nYo from a shell script!\nHola from a nushell script!\nHello from ruby! On Unix-like operating systems, including Linux and MacOS, shebang recipes are executed by saving the recipe body to a file in a temporary directory, marking the file as executable, and executing it. The OS then parses the shebang line into a command line and invokes it, including the path to the file. For example, if a recipe starts with #!/usr/bin/env bash, the final command that the OS runs will be something like /usr/bin/env bash /tmp/PATH_TO_SAVED_RECIPE_BODY. Keep in mind that different operating systems split shebang lines differently. Windows does not support shebang lines. On Windows, just splits the shebang line into a command and arguments, saves the recipe body to a file, and invokes the split command and arguments, adding the path to the saved recipe body as the final argument. For example, on Windows, if a recipe starts with #! py, the final command the OS runs will be something like py C:\\Temp\\PATH_TO_SAVED_RECIPE_BODY.","breadcrumbs":"Introduction » Features » Writing Recipes in Other Languages » Writing Recipes in Other Languages","id":"40","title":"Writing Recipes in Other Languages"},"41":{"body":"If you’re writing a bash shebang recipe, consider adding set -euxo pipefail: foo: #!/usr/bin/env bash set -euxo pipefail hello='Yo' echo \"$hello from Bash!\" It isn’t strictly necessary, but set -euxo pipefail turns on a few useful features that make bash shebang recipes behave more like normal, linewise just recipe: set -e makes bash exit if a command fails. set -u makes bash exit if a variable is undefined. set -x makes bash print each script line before it’s run. set -o pipefail makes bash exit if a command in a pipeline fails. This is bash-specific, so isn’t turned on in normal linewise just recipes. Together, these avoid a lot of shell scripting gotchas. Shebang Recipe Execution on Windows On Windows, shebang interpreter paths containing a / are translated from Unix-style paths to Windows-style paths using cygpath, a utility that ships with Cygwin . For example, to execute this recipe on Windows: echo: #!/bin/sh echo \"Hello!\" The interpreter path /bin/sh will be translated to a Windows-style path using cygpath before being executed. If the interpreter path does not contain a / it will be executed without being translated. This is useful if cygpath is not available, or you wish to pass a Windows-style path to the interpreter.","breadcrumbs":"Introduction » Features » Safer Bash Shebang Recipes » Safer Bash Shebang Recipes","id":"41","title":"Safer Bash Shebang Recipes"},"42":{"body":"Recipe lines are interpreted by the shell, not just, so it’s not possible to set just variables in the middle of a recipe: foo: x := \"hello\" # This doesn't work! echo {{x}} It is possible to use shell variables, but there’s another problem. Every recipe line is run by a new shell instance, so variables set in one line won’t be set in the next: foo: x=hello && echo $x # This works! y=bye echo $y # This doesn't, `y` is undefined here! The best way to work around this is to use a shebang recipe. Shebang recipe bodies are extracted and run as scripts, so a single shell instance will run the whole thing: foo: #!/usr/bin/env bash set -euxo pipefail x=hello echo $x","breadcrumbs":"Introduction » Features » Setting Variables in a Recipe » Setting Variables in a Recipe","id":"42","title":"Setting Variables in a Recipe"},"43":{"body":"Each line of each recipe is executed by a fresh shell, so it is not possible to share environment variables between recipes. Using Python Virtual Environments Some tools, like Python’s venv , require loading environment variables in order to work, making them challenging to use with just. As a workaround, you can execute the virtual environment binaries directly: venv: [ -d foo ] || python3 -m venv foo run: venv ./foo/bin/python3 main.py","breadcrumbs":"Introduction » Features » Sharing Environment Variables Between Recipes » Sharing Environment Variables Between Recipes","id":"43","title":"Sharing Environment Variables Between Recipes"},"44":{"body":"Each recipe line is executed by a new shell, so if you change the working directory on one line, it won’t have an effect on later lines: foo: pwd # This `pwd` will print the same directory… cd bar pwd # …as this `pwd`! There are a couple ways around this. One is to call cd on the same line as the command you want to run: foo: cd bar && pwd The other is to use a shebang recipe. Shebang recipe bodies are extracted and run as scripts, so a single shell instance will run the whole thing, and thus a pwd on one line will affect later lines, just like a shell script: foo: #!/usr/bin/env bash set -euxo pipefail cd bar pwd","breadcrumbs":"Introduction » Features » Changing the Working Directory in a Recipe » Changing the Working Directory in a Recipe","id":"44","title":"Changing