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Switch to fish_indent based syntax highlighting in sphinx docs
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.. highlight:: fish-docs-samples
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docs: Link tutorial immediately
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.. _tutorial:
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Tutorial
========
Why fish?
---------
``fish`` is a fully-equipped command line shell (like bash or zsh) that is smart and user-friendly. ``fish`` supports powerful features like syntax highlighting, autosuggestions, and tab completions that just work, with nothing to learn or configure.
If you want to make your command line more productive, more useful, and more fun, without learning a bunch of arcane syntax and configuration options, then ``fish`` might be just what you're looking for!
Getting started
---------------
Once installed, just type in ``fish`` into your current shell to try it out!
You will be greeted by the standard fish prompt,
which means you are all set up and can start using fish::
> fish
docs: Remove <outp> tags fish_indent_lexer formats lines not starting with a prompt indicator as output, as long as there is a prompt indicator elsewhere. So these tags are useless and wrong. See #5696. [ci skip]
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Welcome to fish, the friendly interactive shell
docs: Remove some more html See #5696. [ci skip]
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Type help for instructions on how to use fish
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
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you@hostname ~>
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This prompt that you see above is the ``fish`` default prompt: it shows your username, hostname, and working directory.
Correction link in doc.
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- to change this prompt see `how to change your prompt <#prompt>`_
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- to switch to fish permanently see `switch your default shell to fish <#switching-to-fish>`_.
docs: don't quote code snippets The added single quotes don't look great in HTML, and it's already clear that the monospaced text is to be interpreted literally.
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From now on, we'll pretend your prompt is just a ``>`` to save space.
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Learning fish
-------------
This tutorial assumes a basic understanding of command line shells and Unix commands, and that you have a working copy of ``fish``.
docs: Remove some more html See #5696. [ci skip]
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If you have a strong understanding of other shells, and want to know what ``fish`` does differently, search for the magic phrase *unlike other shells*, which is used to call out important differences.
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Running Commands
----------------
``fish`` runs commands like other shells: you type a command, followed by its arguments. Spaces are separators::
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
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> echo hello world
docs: Remove <outp> tags fish_indent_lexer formats lines not starting with a prompt indicator as output, as long as there is a prompt indicator elsewhere. So these tags are useless and wrong. See #5696. [ci skip]
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hello world
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docs/tutorial: Misc [ci skip]
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This runs the command `echo` with the arguments `hello` and `world`.
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You can include a literal space in an argument with a backslash, or by using single or double quotes::
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
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> mkdir My\ Files
> cp ~/Some\ File 'My Files'
> ls "My Files"
docs: Remove <outp> tags fish_indent_lexer formats lines not starting with a prompt indicator as output, as long as there is a prompt indicator elsewhere. So these tags are useless and wrong. See #5696. [ci skip]
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Some File
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Commands can be chained with semicolons.
Getting Help
------------
``fish`` has excellent help and man pages. Run ``help`` to open help in a web browser, and ``man`` to open it in a man page. You can also ask for help with a specific command, for example, ``help set`` to open in a web browser, or ``man set`` to see it in the terminal.
::
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
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> man set
docs: Remove <outp> tags fish_indent_lexer formats lines not starting with a prompt indicator as output, as long as there is a prompt indicator elsewhere. So these tags are useless and wrong. See #5696. [ci skip]
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set - handle shell variables
Synopsis...
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Syntax Highlighting
-------------------
docs/tutorial: Replace coloring markup This used to use doxygen's html blocks, which don't have a *direct* equivalent in sphinx in code blocks. Instead of adding this to the pygments highlighter, let's just use some roles. It's a teensy bit awkward as we then use block styling, but we want to add more of our own styling anyway, so we can presumably get this somehow, and these html tags look awkward and confuse people. Fix #6640 [ci skip]
2020-02-22 17:01:05 +00:00
.. role:: red
.. role:: gray
.. role:: underline
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docs/tutorial: Replace coloring markup This used to use doxygen's html blocks, which don't have a *direct* equivalent in sphinx in code blocks. Instead of adding this to the pygments highlighter, let's just use some roles. It's a teensy bit awkward as we then use block styling, but we want to add more of our own styling anyway, so we can presumably get this somehow, and these html tags look awkward and confuse people. Fix #6640 [ci skip]
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You'll quickly notice that ``fish`` performs syntax highlighting as you type. Invalid commands are colored red by default
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docs/tutorial: Replace coloring markup This used to use doxygen's html blocks, which don't have a *direct* equivalent in sphinx in code blocks. Instead of adding this to the pygments highlighter, let's just use some roles. It's a teensy bit awkward as we then use block styling, but we want to add more of our own styling anyway, so we can presumably get this somehow, and these html tags look awkward and confuse people. Fix #6640 [ci skip]
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> :red:`/bin/mkd`
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A command may be invalid because it does not exist, or refers to a file that you cannot execute. When the command becomes valid, it is shown in a different color::
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
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> /bin/mkdir
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docs/tutorial: Replace coloring markup This used to use doxygen's html blocks, which don't have a *direct* equivalent in sphinx in code blocks. Instead of adding this to the pygments highlighter, let's just use some roles. It's a teensy bit awkward as we then use block styling, but we want to add more of our own styling anyway, so we can presumably get this somehow, and these html tags look awkward and confuse people. Fix #6640 [ci skip]
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``fish`` will underline valid file paths as you type them
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docs/tutorial: Replace coloring markup This used to use doxygen's html blocks, which don't have a *direct* equivalent in sphinx in code blocks. Instead of adding this to the pygments highlighter, let's just use some roles. It's a teensy bit awkward as we then use block styling, but we want to add more of our own styling anyway, so we can presumably get this somehow, and these html tags look awkward and confuse people. Fix #6640 [ci skip]
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> cat :underline:`~/somefi`
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docs: don't quote code snippets The added single quotes don't look great in HTML, and it's already clear that the monospaced text is to be interpreted literally.
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This tells you that there exists a file that starts with ``somefi``, which is useful feedback as you type.
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These colors, and many more, can be changed by running ``fish_config``, or by modifying variables directly.
Wildcards
---------
``fish`` supports the familiar wildcard ``*``. To list all JPEG files::
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
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> ls *.jpg
docs: Remove <outp> tags fish_indent_lexer formats lines not starting with a prompt indicator as output, as long as there is a prompt indicator elsewhere. So these tags are useless and wrong. See #5696. [ci skip]
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lena.jpg
meena.jpg
santa maria.jpg
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You can include multiple wildcards::
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
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> ls l*.p*
docs: Remove <outp> tags fish_indent_lexer formats lines not starting with a prompt indicator as output, as long as there is a prompt indicator elsewhere. So these tags are useless and wrong. See #5696. [ci skip]
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lena.png
lesson.pdf
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Especially powerful is the recursive wildcard ** which searches directories recursively::
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
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> ls /var/**.log
docs: Remove <outp> tags fish_indent_lexer formats lines not starting with a prompt indicator as output, as long as there is a prompt indicator elsewhere. So these tags are useless and wrong. See #5696. [ci skip]
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/var/log/system.log
/var/run/sntp.log
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docs: Fix spacing on key combinations
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If that directory traversal is taking a long time, you can :kbd:`Control`\ +\ :kbd:`C` out of it.
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Pipes and Redirections
----------------------
You can pipe between commands with the usual vertical bar::
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
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> echo hello world | wc
1 2 12
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docs/tutorial: Fix `<` typo See #6640
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stdin and stdout can be redirected via the familiar `<` and `>`. stderr is redirected with a `2>`.
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::
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
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> grep fish < /etc/shells > ~/output.txt 2> ~/errors.txt
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Clarify how to redirect stderr into stdout in tutorial
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To redirect stdout and stderr into one file, you need to first redirect stdout, and then stderr into stdout::
> make > make_output.txt 2>&1
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Autosuggestions
---------------
docs/tutorial: Replace coloring markup This used to use doxygen's html blocks, which don't have a *direct* equivalent in sphinx in code blocks. Instead of adding this to the pygments highlighter, let's just use some roles. It's a teensy bit awkward as we then use block styling, but we want to add more of our own styling anyway, so we can presumably get this somehow, and these html tags look awkward and confuse people. Fix #6640 [ci skip]
2020-02-22 17:01:05 +00:00
``fish`` suggests commands as you type, and shows the suggestion to the right of the cursor, in gray. For example
Add tutorial to sphinx docs build
2019-02-25 01:13:01 +00:00
docs/tutorial: Replace coloring markup This used to use doxygen's html blocks, which don't have a *direct* equivalent in sphinx in code blocks. Instead of adding this to the pygments highlighter, let's just use some roles. It's a teensy bit awkward as we then use block styling, but we want to add more of our own styling anyway, so we can presumably get this somehow, and these html tags look awkward and confuse people. Fix #6640 [ci skip]
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> :red:`/bin/h`:gray:`ostname`
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docs/tutorial: Replace coloring markup This used to use doxygen's html blocks, which don't have a *direct* equivalent in sphinx in code blocks. Instead of adding this to the pygments highlighter, let's just use some roles. It's a teensy bit awkward as we then use block styling, but we want to add more of our own styling anyway, so we can presumably get this somehow, and these html tags look awkward and confuse people. Fix #6640 [ci skip]
2020-02-22 17:01:05 +00:00
It knows about paths and options
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docs/tutorial: Replace coloring markup This used to use doxygen's html blocks, which don't have a *direct* equivalent in sphinx in code blocks. Instead of adding this to the pygments highlighter, let's just use some roles. It's a teensy bit awkward as we then use block styling, but we want to add more of our own styling anyway, so we can presumably get this somehow, and these html tags look awkward and confuse people. Fix #6640 [ci skip]
2020-02-22 17:01:05 +00:00
`> grep --i`:gray:`gnore-case`
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docs/tutorial: Replace coloring markup This used to use doxygen's html blocks, which don't have a *direct* equivalent in sphinx in code blocks. Instead of adding this to the pygments highlighter, let's just use some roles. It's a teensy bit awkward as we then use block styling, but we want to add more of our own styling anyway, so we can presumably get this somehow, and these html tags look awkward and confuse people. Fix #6640 [ci skip]
2020-02-22 17:01:05 +00:00
And history too. Type a command once, and you can re-summon it by just typing a few letters
Add tutorial to sphinx docs build
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docs/tutorial: Replace coloring markup This used to use doxygen's html blocks, which don't have a *direct* equivalent in sphinx in code blocks. Instead of adding this to the pygments highlighter, let's just use some roles. It's a teensy bit awkward as we then use block styling, but we want to add more of our own styling anyway, so we can presumably get this somehow, and these html tags look awkward and confuse people. Fix #6640 [ci skip]
2020-02-22 17:01:05 +00:00
> :red:`r`:gray:`sync -avze ssh . myname@somelonghost.com:/some/long/path/doo/dee/doo/dee/doo`
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docs: Fix spacing on key combinations
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To accept the autosuggestion, hit :kbd:`→` (right arrow) or :kbd:`Control`\ +\ :kbd:`F`. To accept a single word of the autosuggestion, :kbd:`Alt`\ +\ :kbd:`→` (right arrow). If the autosuggestion is not what you want, just ignore it.
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Tab Completions
---------------
``fish`` comes with a rich set of tab completions, that work "out of the box."
docs/tutorial: Replace coloring markup This used to use doxygen's html blocks, which don't have a *direct* equivalent in sphinx in code blocks. Instead of adding this to the pygments highlighter, let's just use some roles. It's a teensy bit awkward as we then use block styling, but we want to add more of our own styling anyway, so we can presumably get this somehow, and these html tags look awkward and confuse people. Fix #6640 [ci skip]
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Press :kbd:`Tab`, and ``fish`` will attempt to complete the command, argument, or path
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docs/tutorial: Replace coloring markup This used to use doxygen's html blocks, which don't have a *direct* equivalent in sphinx in code blocks. Instead of adding this to the pygments highlighter, let's just use some roles. It's a teensy bit awkward as we then use block styling, but we want to add more of our own styling anyway, so we can presumably get this somehow, and these html tags look awkward and confuse people. Fix #6640 [ci skip]
2020-02-22 17:01:05 +00:00
> :red:`/pri` :kbd:`Tab` => /private/
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docs/tutorial: Replace coloring markup This used to use doxygen's html blocks, which don't have a *direct* equivalent in sphinx in code blocks. Instead of adding this to the pygments highlighter, let's just use some roles. It's a teensy bit awkward as we then use block styling, but we want to add more of our own styling anyway, so we can presumably get this somehow, and these html tags look awkward and confuse people. Fix #6640 [ci skip]
2020-02-22 17:01:05 +00:00
If there's more than one possibility, it will list them
Add tutorial to sphinx docs build
2019-02-25 01:13:01 +00:00
docs/tutorial: Replace coloring markup This used to use doxygen's html blocks, which don't have a *direct* equivalent in sphinx in code blocks. Instead of adding this to the pygments highlighter, let's just use some roles. It's a teensy bit awkward as we then use block styling, but we want to add more of our own styling anyway, so we can presumably get this somehow, and these html tags look awkward and confuse people. Fix #6640 [ci skip]
2020-02-22 17:01:05 +00:00
> :red:`~/stuff/s` :kbd:`Tab`
~/stuff/script.sh (Executable, 4.8kB) ~/stuff/sources/ (Directory)
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Hit tab again to cycle through the possibilities.
``fish`` can also complete many commands, like git branches::
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
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> git merge pr :kbd:`Tab` => git merge prompt_designer
> git checkout b :kbd:`Tab`
builtin_list_io_merge (Branch) builtin_set_color (Branch) busted_events (Tag)
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Try hitting tab and see what ``fish`` can do!
Variables
---------
Like other shells, a dollar sign performs variable substitution::
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
2019-11-04 19:08:45 +00:00
> echo My home directory is $HOME
docs: Remove <outp> tags fish_indent_lexer formats lines not starting with a prompt indicator as output, as long as there is a prompt indicator elsewhere. So these tags are useless and wrong. See #5696. [ci skip]
2019-04-30 10:19:04 +00:00
My home directory is /home/tutorial
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docs/tutorial: Misc [ci skip]
2019-06-06 17:38:41 +00:00
Variable substitution also happens in double quotes, but not single quotes::
Add tutorial to sphinx docs build
2019-02-25 01:13:01 +00:00
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
2019-11-04 19:08:45 +00:00
> echo "My current directory is $PWD"
docs: Remove <outp> tags fish_indent_lexer formats lines not starting with a prompt indicator as output, as long as there is a prompt indicator elsewhere. So these tags are useless and wrong. See #5696. [ci skip]
2019-04-30 10:19:04 +00:00
My current directory is /home/tutorial
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
2019-11-04 19:08:45 +00:00
> echo 'My current directory is $PWD'
docs: Remove <outp> tags fish_indent_lexer formats lines not starting with a prompt indicator as output, as long as there is a prompt indicator elsewhere. So these tags are useless and wrong. See #5696. [ci skip]
2019-04-30 10:19:04 +00:00
My current directory is $PWD
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2019-02-25 01:13:01 +00:00
docs/tutorial: Mention VAR=VAL syntax That's the thing we're replacing, so we should mention it. [ci skip]
2019-06-06 17:17:49 +00:00
Unlike other shells, ``fish`` has no dedicated `VARIABLE=VALUE` syntax for setting variables. Instead it has an ordinary command: ``set``, which takes a variable name, and then its value.
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::
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
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> set name 'Mister Noodle'
> echo $name
docs: Remove <outp> tags fish_indent_lexer formats lines not starting with a prompt indicator as output, as long as there is a prompt indicator elsewhere. So these tags are useless and wrong. See #5696. [ci skip]
2019-04-30 10:19:04 +00:00
Mister Noodle
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(Notice the quotes: without them, ``Mister`` and ``Noodle`` would have been separate arguments, and ``$name`` would have been made into a list of two elements.)
Unlike other shells, variables are not further split after substitution::
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
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> mkdir $name
> ls
docs: Remove <outp> tags fish_indent_lexer formats lines not starting with a prompt indicator as output, as long as there is a prompt indicator elsewhere. So these tags are useless and wrong. See #5696. [ci skip]
2019-04-30 10:19:04 +00:00
Mister Noodle
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In bash, this would have created two directories "Mister" and "Noodle". In ``fish``, it created only one: the variable had the value "Mister Noodle", so that is the argument that was passed to ``mkdir``, spaces and all. Other shells use the term "arrays", rather than lists.
docs/tutorial: Rewrite exports section See #5920. [ci skip]
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You can erase (or "delete") a variable with ``-e`` or ``--erase``
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::
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
2019-11-04 19:08:45 +00:00
> set -e MyVariable
> env | grep MyVariable
docs/tutorial: Rewrite exports section See #5920. [ci skip]
2019-06-06 17:26:54 +00:00
(no output)
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docs/tutorial: Rewrite exports section See #5920. [ci skip]
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Exports (Shell Variables)
-------------------------
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docs/tutorial: Rewrite exports section See #5920. [ci skip]
2019-06-06 17:26:54 +00:00
Sometimes you need to have a variable available to an external command, often as a setting. For example many programs like `git` or `man` read the `$PAGER` variable to figure out your preferred pager (the program that lets you scroll text). Other variables used like this include `$BROWSER`, `$LANG` (to configure your language) and `$PATH`. You'll note these are written in ALLCAPS, but that's just a convention.
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2019-02-25 01:13:01 +00:00
docs/tutorial: Rewrite exports section See #5920. [ci skip]
2019-06-06 17:26:54 +00:00
To give a variable to an external command, it needs to be "exported". Unlike other shells, ``fish`` does not have an export command. Instead, a variable is exported via an option to ``set``, either ``--export`` or just ``-x``.
Add tutorial to sphinx docs build
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::
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
2019-11-04 19:08:45 +00:00
> set -x MyVariable SomeValue
> env | grep MyVariable
docs/tutorial: Rewrite exports section See #5920. [ci skip]
2019-06-06 17:26:54 +00:00
MyVariable=SomeValue
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2019-02-25 01:13:01 +00:00
docs/tutorial: Rewrite exports section See #5920. [ci skip]
2019-06-06 17:26:54 +00:00
It can also be unexported with ``--unexport`` or ``-u``.
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2019-02-25 01:13:01 +00:00
docs/tutorial: Fix list link [ci skip]
2019-06-06 20:52:14 +00:00
.. _tut_lists:
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Lists
-----
The ``set`` command above used quotes to ensure that ``Mister Noodle`` was one argument. If it had been two arguments, then ``name`` would have been a list of length 2. In fact, all variables in ``fish`` are really lists, that can contain any number of values, or none at all.
Some variables, like ``$PWD``, only have one value. By convention, we talk about that variable's value, but we really mean its first (and only) value.
Other variables, like ``$PATH``, really do have multiple values. During variable expansion, the variable expands to become multiple arguments::
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
2019-11-04 19:08:45 +00:00
> echo $PATH
docs: Remove <outp> tags fish_indent_lexer formats lines not starting with a prompt indicator as output, as long as there is a prompt indicator elsewhere. So these tags are useless and wrong. See #5696. [ci skip]
2019-04-30 10:19:04 +00:00
/usr/bin /bin /usr/sbin /sbin /usr/local/bin
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2019-02-25 01:13:01 +00:00
Docs: Document path vars more Fixes #5741. [ci skip]
2019-04-30 11:18:56 +00:00
Variables whose name ends in "PATH" are automatically split on colons to become lists. They are joined using colons when exported to subcommands. This is for compatibility with other tools, which expect $PATH to use colons. You can also explicitly add this quirk to a variable with `set --path`, or remove it with `set --unpath`.
Add tutorial to sphinx docs build
2019-02-25 01:13:01 +00:00
Lists cannot contain other lists: there is no recursion. A variable is a list of strings, full stop.
Get the length of a list with ``count``::
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
2019-11-04 19:08:45 +00:00
> count $PATH
docs: Remove <outp> tags fish_indent_lexer formats lines not starting with a prompt indicator as output, as long as there is a prompt indicator elsewhere. So these tags are useless and wrong. See #5696. [ci skip]
2019-04-30 10:19:04 +00:00
5
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You can append (or prepend) to a list by setting the list to itself, with some additional arguments. Here we append /usr/local/bin to $PATH::
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
2019-11-04 19:08:45 +00:00
> set PATH $PATH /usr/local/bin
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You can access individual elements with square brackets. Indexing starts at 1 from the beginning, and -1 from the end::
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
2019-11-04 19:08:45 +00:00
> echo $PATH
docs: Remove <outp> tags fish_indent_lexer formats lines not starting with a prompt indicator as output, as long as there is a prompt indicator elsewhere. So these tags are useless and wrong. See #5696. [ci skip]
2019-04-30 10:19:04 +00:00
/usr/bin /bin /usr/sbin /sbin /usr/local/bin
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
2019-11-04 19:08:45 +00:00
> echo $PATH[1]
docs: Remove <outp> tags fish_indent_lexer formats lines not starting with a prompt indicator as output, as long as there is a prompt indicator elsewhere. So these tags are useless and wrong. See #5696. [ci skip]
2019-04-30 10:19:04 +00:00
/usr/bin
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
2019-11-04 19:08:45 +00:00
> echo $PATH[-1]
docs: Remove <outp> tags fish_indent_lexer formats lines not starting with a prompt indicator as output, as long as there is a prompt indicator elsewhere. So these tags are useless and wrong. See #5696. [ci skip]
2019-04-30 10:19:04 +00:00
/usr/local/bin
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You can also access ranges of elements, known as "slices:"
::
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
2019-11-04 19:08:45 +00:00
> echo $PATH[1..2]
docs: Remove <outp> tags fish_indent_lexer formats lines not starting with a prompt indicator as output, as long as there is a prompt indicator elsewhere. So these tags are useless and wrong. See #5696. [ci skip]
2019-04-30 10:19:04 +00:00
/usr/bin /bin
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
2019-11-04 19:08:45 +00:00
> echo $PATH[-1..2]
docs: Remove <outp> tags fish_indent_lexer formats lines not starting with a prompt indicator as output, as long as there is a prompt indicator elsewhere. So these tags are useless and wrong. See #5696. [ci skip]
2019-04-30 10:19:04 +00:00
/usr/local/bin /sbin /usr/sbin /bin
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2019-02-25 01:13:01 +00:00
You can iterate over a list (or a slice) with a for loop::
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
2019-11-04 19:08:45 +00:00
> for val in $PATH
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echo "entry: $val"
end
docs: Remove <outp> tags fish_indent_lexer formats lines not starting with a prompt indicator as output, as long as there is a prompt indicator elsewhere. So these tags are useless and wrong. See #5696. [ci skip]
2019-04-30 10:19:04 +00:00
entry: /usr/bin/
entry: /bin
entry: /usr/sbin
entry: /sbin
entry: /usr/local/bin
Add tutorial to sphinx docs build
2019-02-25 01:13:01 +00:00
docs: Fix refs to cartesian product There's an explicit label for "cartesian-product", but the title is "Cartesian Product*s*". So linking via with `thing <#link>`_ links the title, so without the "s" it doesn't work. From what I know, linking via :ref:`thing <label>` is preferred and works better with other exports and across files? I think I should take a doc holiday. [ci skip]
2019-04-09 12:06:54 +00:00
Lists adjacent to other lists or strings are expanded as :ref:`cartesian products <cartesian-product>` unless quoted (see :ref:`Variable expansion <expand-variable>`)::
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2019-02-25 01:13:01 +00:00
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
2019-11-04 19:08:45 +00:00
> set a 1 2 3
> set 1 a b c
> echo $a$1
docs: Remove <outp> tags fish_indent_lexer formats lines not starting with a prompt indicator as output, as long as there is a prompt indicator elsewhere. So these tags are useless and wrong. See #5696. [ci skip]
2019-04-30 10:19:04 +00:00
1a 2a 3a 1b 2b 3b 1c 2c 3c
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
2019-11-04 19:08:45 +00:00
> echo $a" banana"
docs: Remove <outp> tags fish_indent_lexer formats lines not starting with a prompt indicator as output, as long as there is a prompt indicator elsewhere. So these tags are useless and wrong. See #5696. [ci skip]
2019-04-30 10:19:04 +00:00
1 banana 2 banana 3 banana
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
2019-11-04 19:08:45 +00:00
> echo "$a banana"
docs: Remove <outp> tags fish_indent_lexer formats lines not starting with a prompt indicator as output, as long as there is a prompt indicator elsewhere. So these tags are useless and wrong. See #5696. [ci skip]
2019-04-30 10:19:04 +00:00
1 2 3 banana
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2019-02-25 01:13:01 +00:00
docs: Fix reference syntax Fixes #5776. [ci skip]
2019-03-30 19:27:30 +00:00
This is similar to `Brace expansion <index#expand-brace>`__.
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Command Substitutions
---------------------
Command substitutions use the output of one command as an argument to another. Unlike other shells, ``fish`` does not use backticks `` for command substitutions. Instead, it uses parentheses::
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
2019-11-04 19:08:45 +00:00
> echo In (pwd), running (uname)
docs: Remove <outp> tags fish_indent_lexer formats lines not starting with a prompt indicator as output, as long as there is a prompt indicator elsewhere. So these tags are useless and wrong. See #5696. [ci skip]
2019-04-30 10:19:04 +00:00
In /home/tutorial, running FreeBSD
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A common idiom is to capture the output of a command in a variable::
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
2019-11-04 19:08:45 +00:00
> set os (uname)
> echo $os
docs: Remove <outp> tags fish_indent_lexer formats lines not starting with a prompt indicator as output, as long as there is a prompt indicator elsewhere. So these tags are useless and wrong. See #5696. [ci skip]
2019-04-30 10:19:04 +00:00
Linux
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Command substitutions are not expanded within quotes. Instead, you can temporarily close the quotes, add the command substitution, and reopen them, all in the same argument::
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
2019-11-04 19:08:45 +00:00
> touch "testing_"(date +%s)".txt"
> ls *.txt
docs: Remove <outp> tags fish_indent_lexer formats lines not starting with a prompt indicator as output, as long as there is a prompt indicator elsewhere. So these tags are useless and wrong. See #5696. [ci skip]
2019-04-30 10:19:04 +00:00
testing_1360099791.txt
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Unlike other shells, fish does not split command substitutions on any whitespace (like spaces or tabs), only newlines. This can be an issue with commands like ``pkg-config`` that print what is meant to be multiple arguments on a single line. To split it on spaces too, use ``string split``.
::
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
2019-11-04 19:08:45 +00:00
> printf '%s\n' (pkg-config --libs gio-2.0)
docs: Remove <outp> tags fish_indent_lexer formats lines not starting with a prompt indicator as output, as long as there is a prompt indicator elsewhere. So these tags are useless and wrong. See #5696. [ci skip]
2019-04-30 10:19:04 +00:00
-lgio-2.0 -lgobject-2.0 -lglib-2.0
Suggest string split -n for separating on spaces. At least on some versions/systems, pkg-config outputs a trailing space. Since the usually-desired behavior isn't to have a blank argument, recommend using `string split -n` instead of `string split`. Fixes #6836. [ci skip]
2020-03-30 17:17:51 +00:00
> printf '%s\n' (pkg-config --libs gio-2.0 | string split -n " ")
docs: Remove <outp> tags fish_indent_lexer formats lines not starting with a prompt indicator as output, as long as there is a prompt indicator elsewhere. So these tags are useless and wrong. See #5696. [ci skip]
2019-04-30 10:19:04 +00:00
-lgio-2.0
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-lgobject-2.0
docs: Remove <outp> tags fish_indent_lexer formats lines not starting with a prompt indicator as output, as long as there is a prompt indicator elsewhere. So these tags are useless and wrong. See #5696. [ci skip]
2019-04-30 10:19:04 +00:00
-lglib-2.0
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2019-02-25 01:13:01 +00:00
docs: fix a few links - add missing links for some commands (control flow section) - fix broken links that use the old syntax (#tut_ links) - miscellaneous fixing of backticks/emphasis
2020-07-17 18:22:57 +00:00
.. _tut_semicolon:
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Separating Commands (Semicolon)
-------------------------------
Like other shells, fish allows multiple commands either on separate lines or the same line.
To write them on the same line, use the semicolon (";"). That means the following two examples are equivalent::
echo fish; echo chips
# or
echo fish
echo chips
docs/tutorial: Put exit status with combiners and conditionals It was awkwardly sandwhiched inbetween variables and exports. [ci skip]
2019-06-06 17:17:09 +00:00
Exit Status
-----------
Change natural number to non-negative integer (#7161) * natural → whole * positive whole * positive whole number → non-negative integer
2020-06-29 18:26:53 +00:00
When a command exits, it returns a status code as a non-negative integer.
docs/tutorial: Rewrite exit status section We've kinda forgotten the "tutorial" part of this. [ci skip]
2019-06-06 17:38:19 +00:00
docs/tutorial: Put exit status with combiners and conditionals It was awkwardly sandwhiched inbetween variables and exports. [ci skip]
2019-06-06 17:17:09 +00:00
Unlike other shells, ``fish`` stores the exit status of the last command in ``$status`` instead of ``$?``.
::
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
2019-11-04 19:08:45 +00:00
> false
> echo $status
docs/tutorial: Put exit status with combiners and conditionals It was awkwardly sandwhiched inbetween variables and exports. [ci skip]
2019-06-06 17:17:09 +00:00
1
Revert "docs/tutorial: Fix duplicate sentence" This reverts commit 9d1129f14cada98bb213605f4c7e4600eff315b6. Probably a bad rebase, at the time this appeared on master the sentence was already removed.
2020-06-11 16:40:05 +00:00
This indicates how the command fared - 0 usually means success, while the others signify kinds of failure. For instance fish's ``set --query`` returns the number of variables it queried that weren't set - ``set --query PATH`` usually returns 0, ``set --query arglbargl boogagoogoo`` usually returns 2.
docs/tutorial: Rewrite exit status section We've kinda forgotten the "tutorial" part of this. [ci skip]
2019-06-06 17:38:19 +00:00
There is also a ``$pipestatus`` list variable for the exit statuses [#]_ of processes in a pipe.
docs/tutorial: Put exit status with combiners and conditionals It was awkwardly sandwhiched inbetween variables and exports. [ci skip]
2019-06-06 17:17:09 +00:00
docs/tutorial: Rewrite exit status section We've kinda forgotten the "tutorial" part of this. [ci skip]
2019-06-06 17:38:19 +00:00
.. [#] or "stati" if you prefer, or "statūs" if you've time-travelled from ancient Rome or work as a latin teacher
docs/tutorial: Put exit status with combiners and conditionals It was awkwardly sandwhiched inbetween variables and exports. [ci skip]
2019-06-06 17:17:09 +00:00
Correct tut_combiners anchor to tut-combiners dash is preferred in the tutorial. This fixes a broken link from the main help page.
2020-07-31 18:53:26 +00:00
.. _tut-combiners:
docs: fix a few links - add missing links for some commands (control flow section) - fix broken links that use the old syntax (#tut_ links) - miscellaneous fixing of backticks/emphasis
2020-07-17 18:22:57 +00:00
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2019-02-25 01:13:01 +00:00
Combiners (And, Or, Not)
------------------------
docs: Remove &foo; escapes I always hated these. [ci skip]
2019-04-06 21:33:07 +00:00
fish supports the familiar ``&&`` and ``||`` to combine commands, and ``!`` to negate them::
Add tutorial to sphinx docs build
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docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
2019-11-04 19:08:45 +00:00
> ./configure && make && sudo make install
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2019-02-25 01:13:01 +00:00
docs: fix a few links - add missing links for some commands (control flow section) - fix broken links that use the old syntax (#tut_ links) - miscellaneous fixing of backticks/emphasis
2020-07-17 18:22:57 +00:00
Here, ``make`` is only executed if ``./configure`` succeeds (returns 0), and ``sudo make install`` is only executed if both ``./configure`` and ``make`` succeed.
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2019-02-25 01:13:01 +00:00
docs: fix a few links - add missing links for some commands (control flow section) - fix broken links that use the old syntax (#tut_ links) - miscellaneous fixing of backticks/emphasis
2020-07-17 18:22:57 +00:00
fish also supports :ref:`and <cmd-and>`, :ref:`or <cmd-or>`, and :ref:`not <cmd-not>`. The first two are job modifiers and have lower precedence. Example usage::
Add tutorial to sphinx docs build
2019-02-25 01:13:01 +00:00
docs/tutorial: Fix formatting This removes the explicit html coloring that was used in the tutorial. Where necessary we just add pseudo-html like `<red>...</red>` to explain it to the users. I don't know how to reintroduce coloring here, but it's not super important as the user can always just check for themselves. See #5696 [ci skip]
2019-11-04 19:08:45 +00:00
> cp file1.txt file1_bak.txt && cp file2.txt file2_bak.txt ; and echo "Backup successful"; or echo "Backup failed"
docs: Remove <outp> tags fish_indent_lexer formats lines not starting with a prompt indicator as output, as long as there is a prompt indicator elsewhere. So these tags are useless and wrong. See #5696. [ci skip]
2019-04-30 10:19:04 +00:00
Backup failed
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2019-02-25 01:13:01 +00:00
docs: fix a few links - add missing links for some commands (control flow section) - fix broken links that use the old syntax (#tut_ links) - miscellaneous fixing of backticks/emphasis
2020-07-17 18:22:57 +00:00
As mentioned in :ref:`the section on the semicolon <tut_semicolon>`, this can also be written in multiple lines, like so::
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cp file1.txt file1_bak.txt && cp file2.txt file2_bak.txt
and echo "Backup successful"
or echo "Backup failed"
docs: More on conditionals directly It's weird to force people to go to the separate pages, at least give some simple examples here and link to the tutorial. [ci skip]
2020-07-24 15:17:39 +00:00
.. _tut-conditionals:
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2019-02-25 01:13:01 +00:00
Conditionals (If, Else, Switch)
-------------------------------
docs: fix a few links - add missing links for some commands (control flow section) - fix broken links that use the old syntax (#tut_ links) - miscellaneous fixing of backticks/emphasis
2020-07-17 18:22:57 +00:00
Use :ref:`if <cmd-if>` and :ref:`else <cmd-else>` to conditionally execute code, based on the exit status of a command.
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::
if grep fish /etc/shells
echo Found fish
else if grep bash /etc/shells
echo Found bash
else
echo Got nothing
end
docs: Use command labels [ci skip]
2019-03-31 09:07:59 +00:00
To compare strings or numbers or check file properties (whether a file exists or is writeable and such), use :ref:`test <cmd-test>`, like
Add tutorial to sphinx docs build
2019-02-25 01:13:01 +00:00
::
if test "$fish" = "flounder"
echo FLOUNDER
end
# or
if test "$number" -gt 5
echo $number is greater than five
else
echo $number is five or less
end
docs/tutorial: Expand [ci skip]
2019-06-06 18:00:11 +00:00
# or
if test -e /etc/hosts # is true if the path /etc/hosts exists - it could be a file or directory or symlink (or possibly something else).
echo We most likely have a hosts file
else
echo We do not have a hosts file
end
Add tutorial to sphinx docs build
2019-02-25 01:13:01 +00:00
Correct tut_combiners anchor to tut-combiners dash is preferred in the tutorial. This fixes a broken link from the main help page.
2020-07-31 18:53:26 +00:00
:ref:`Combiners <tut-combiners>` can also be used to make more complex conditions, like
Add tutorial to sphinx docs build
2019-02-25 01:13:01 +00:00
::
if grep fish /etc/shells; and command -sq fish
echo fish is installed and configured
end
docs: fix a few links - add missing links for some commands (control flow section) - fix broken links that use the old syntax (#tut_ links) - miscellaneous fixing of backticks/emphasis
2020-07-17 18:22:57 +00:00
For even more complex conditions, use :ref:`begin <cmd-begin>` and :ref:`end <cmd-end>` to group parts of them.
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2019-02-25 01:13:01 +00:00
docs: fix a few links - add missing links for some commands (control flow section) - fix broken links that use the old syntax (#tut_ links) - miscellaneous fixing of backticks/emphasis
2020-07-17 18:22:57 +00:00
There is also a :ref:`switch <cmd-switch>` command::
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switch (uname)
case Linux
echo Hi Tux!
case Darwin
echo Hi Hexley!
case FreeBSD NetBSD DragonFly
echo Hi Beastie!
case '*'
echo Hi, stranger!
end
docs: fix a few links - add missing links for some commands (control flow section) - fix broken links that use the old syntax (#tut_ links) - miscellaneous fixing of backticks/emphasis
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Note that :ref:`case <cmd-case>` does not fall through, and can accept multiple arguments or (quoted) wildcards.
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Functions
---------
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A fish function is a list of commands, which may optionally take arguments. Unlike other shells, arguments are not passed in "numbered variables" like ``$1``, but instead in a single list ``$argv``. To create a function, use the :ref:`function <cmd-function>` builtin::
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> function say_hello
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echo Hello $argv
end
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> say_hello
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Hello
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> say_hello everybody!
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Hello everybody!
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Unlike other shells, fish does not have aliases or special prompt syntax. Functions take their place.
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You can list the names of all functions with the :ref:`functions <cmd-functions>` builtin (note the plural!). fish starts out with a number of functions::
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> functions
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N_, abbr, alias, bg, cd, cdh, contains_seq, delete-or-exit, dirh, dirs, disown, down-or-search, edit_command_buffer, export, fg, fish_add_path, fish_breakpoint_prompt, fish_clipboard_copy, fish_clipboard_paste, fish_config, fish_default_key_bindings, fish_default_mode_prompt, fish_git_prompt, fish_hg_prompt, fish_hybrid_key_bindings, fish_indent, fish_is_root_user, fish_job_summary, fish_key_reader, fish_md5, fish_mode_prompt, fish_npm_helper, fish_opt, fish_print_git_action, fish_print_hg_root, fish_prompt, fish_sigtrap_handler, fish_svn_prompt, fish_title, fish_update_completions, fish_vcs_prompt, fish_vi_cursor, fish_vi_key_bindings, funced, funcsave, grep, help, history, hostname, isatty, kill, la, ll, ls, man, nextd, nextd-or-forward-word, open, popd, prevd, prevd-or-backward-word, prompt_hostname, prompt_pwd, psub, pushd, realpath, seq, setenv, suspend, trap, type, umask, up-or-search, vared, wait
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You can see the source for any function by passing its name to ``functions``::
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> functions ls
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function ls --description 'List contents of directory'
command ls -G $argv
end
Loops
-----
While loops::
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> while true
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echo "Loop forever"
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end
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Loop forever
Loop forever
Loop forever
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... # yes, this really will loop forever. Unless you abort it with ctrl-c.
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For loops can be used to iterate over a list. For example, a list of files::
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> for file in *.txt
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cp $file $file.bak
end
Iterating over a list of numbers can be done with ``seq``::
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> for x in (seq 5)
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touch file_$x.txt
end
Prompt
------
Unlike other shells, there is no prompt variable like PS1. To display your prompt, ``fish`` executes a function with the name ``fish_prompt``, and its output is used as the prompt.
You can define your own prompt::
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> function fish_prompt
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echo "New Prompt % "
end
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New Prompt %
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docs/tutorial: Fix prompt display This displays a colored prompt, which we emulate by adding explicit roles that are translated to css classes. For other things, like "eror" this might not be enough because those often need the rest of the line to still be styled, and I've not found a way to add some explicit styling to a code block. See #5696. [ci skip]
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.. role:: purple
.. role:: yellow
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Multiple lines are OK. Colors can be set via ``set_color``, passing it named ANSI colors, or hex RGB values::
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> function fish_prompt
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set_color purple
date "+%m/%d/%y"
set_color FF0
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echo (pwd) '>' (set_color normal)
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end
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will look like
| :purple:`02/06/13`
| :yellow:`/home/tutorial >`
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You can choose among some sample prompts by running ``fish_config prompt``. ``fish`` also supports RPROMPT through ``fish_right_prompt``.
$PATH
-----
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``$PATH`` is an environment variable containing the directories that ``fish`` searches for commands. Unlike other shells, $PATH is a :ref:`list <tut_lists>`, not a colon-delimited string.
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To prepend /usr/local/bin and /usr/sbin to ``$PATH``, you can write::
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> set PATH /usr/local/bin /usr/sbin $PATH
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To remove /usr/local/bin from ``$PATH``, you can write::
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> set PATH (string match -v /usr/local/bin $PATH)
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For compatibility with other shells and external commands, $PATH is a :ref:`path variable<variables-path>`, and so will be joined with colons (not spaces) when you quote it:
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> echo "$PATH"
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/usr/local/sbin:/usr/local/bin:/usr/bin
and it will be exported like that, and when fish starts it splits the $PATH it receives into a list on colon.
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You can do so directly in ``config.fish``, like you might do in other shells with ``.profile``. See :ref:`this example <path_example>`.
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A faster way is to use the :ref:`fish_add_path <cmd-fish_add_path>` function, which adds given directories to the path if they aren't already included. It does this by modifying the ``$fish_user_paths`` :ref:`universal variable <tut-universal>`, which is automatically prepended to ``$PATH``. For example, to permanently add ``/usr/local/bin`` to your ``$PATH``, you could write::
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> fish_add_path /usr/local/bin
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The advantage is that you don't have to go mucking around in files: just run this once at the command line, and it will affect the current session and all future instances too. You can also add this line to :ref:`config.fish <tut-config>`, as it only adds the component if necessary.
Or you can modify $fish_user_paths yourself, but you should be careful *not* to append to it unconditionally in config.fish, or it will grow longer and longer.
.. _tut-config:
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Startup (Where's .bashrc?)
--------------------------
``fish`` starts by executing commands in ``~/.config/fish/config.fish``. You can create it if it does not exist.
It is possible to directly create functions and variables in ``config.fish`` file, using the commands shown above. For example:
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.. _path_example:
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::
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> cat ~/.config/fish/config.fish
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set -x PATH $PATH /sbin/
function ll
ls -lh $argv
end
However, it is more common and efficient to use autoloading functions and universal variables.
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If you want to organize your configuration, fish also reads commands in .fish files in ``~/.config/fish/conf.d/``. See :ref:`initialization <initialization>` for the details.
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Autoloading Functions
---------------------
When ``fish`` encounters a command, it attempts to autoload a function for that command, by looking for a file with the name of that command in ``~/.config/fish/functions/``.
For example, if you wanted to have a function ``ll``, you would add a text file ``ll.fish`` to ``~/.config/fish/functions``::
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> cat ~/.config/fish/functions/ll.fish
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function ll
ls -lh $argv
end
This is the preferred way to define your prompt as well::
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> cat ~/.config/fish/functions/fish_prompt.fish
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function fish_prompt
echo (pwd) "> "
end
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See the documentation for :ref:`funced <cmd-funced>` and :ref:`funcsave <cmd-funcsave>` for ways to create these files automatically, and :ref:`$fish_function_path <syntax-function-autoloading>` to control their location.
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.. _tut-universal:
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Universal Variables
-------------------
A universal variable is a variable whose value is shared across all instances of ``fish``, now and in the future – even after a reboot. You can make a variable universal with ``set -U``::
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> set -U EDITOR vim
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Now in another shell::
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> echo $EDITOR
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vim
.. _switching-to-fish:
Switching to fish?
------------------
If you wish to use fish (or any other shell) as your default shell,
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you need to enter your new shell's executable in two places.
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Add the shell to ``/etc/shells`` with::
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> echo /usr/local/bin/fish | sudo tee -a /etc/shells
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Change your default shell with::
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> chsh -s /usr/local/bin/fish
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(To change it back to another shell, just substitute ``/usr/local/bin/fish``
with ``/bin/bash``, ``/bin/tcsh`` or ``/bin/zsh`` as appropriate in the steps above.)
Ready for more?
---------------
Disavow IRC channel I don't know of any fish dev on there, so it's not a good channel to reach us and I have no idea how good it is, so it's best to just ditch it.
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If you want to learn more about fish, there is :ref:`lots of detailed documentation <intro>`, the `official gitter channel <https://gitter.im/fish-shell/fish-shell>`__, an `official mailing list <https://lists.sourceforge.net/lists/listinfo/fish-users>`__, and the `github page <https://github.com/fish-shell/fish-shell/>`__.
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