doc_src/cmds/string-trim.rst

string-trim - remove trailing whitespace
========================================

Synopsis
--------

.. BEGIN SYNOPSIS

.. synopsis::

    string trim [-l | --left] [-r | --right] [(-c | --chars) CHARS]
                [-q | --quiet] [STRING ...]

.. END SYNOPSIS

Description
-----------

.. BEGIN DESCRIPTION

``string trim`` removes leading and trailing whitespace from each *STRING*. If **-l** or **--left** is given, only leading whitespace is removed. If **-r** or **--right** is given, only trailing whitespace is trimmed.

The **-c** or **--chars** switch causes the set of characters in *CHARS* to be removed instead of whitespace. This is a set of characters, not a string - if you pass ``-c foo``, it will remove any "f" or "o", not just "foo" as a whole.

Exit status: 0 if at least one character was trimmed, or 1 otherwise.

.. END DESCRIPTION

Examples
--------

.. BEGIN EXAMPLES

::

    >_ string trim ' abc  '
    abc

    >_ string trim --right --chars=yz xyzzy zany
    x
    zan


.. END EXAMPLES
Add individual documentation pages for string's subcommands This adds string-x.rst for each subcommand x of string. The main page (string.rst) is not changed, except that examples are shown directly after each subcommand. The subcommand sections in string.rst are created by textual inclusion of parts of the string-x.rst files. Subcommand man pages can be viewed with either of: ``` man string collect man string-collect string collect <press F1 or Alt-h> string collect -h ``` While `string -h ...` still prints the full help. Closes #5968 2019-10-27 10:56:24 +01:00			`string-trim - remove trailing whitespace`
			`========================================`

			`Synopsis`
			`--------`

			`.. BEGIN SYNOPSIS`

docs synopsis: add HTML highlighing and automate manpage markup Recent synopsis changes move from literal code blocks to [RST line blocks]. This does not translate well to HTML: it's not rendered in monospace, so aligment is lost. Additionally, we don't get syntax highlighting in HTML, which adds differences to our code samples which are highlighted. We hard-wrap synopsis lines (like code blocks). To align continuation lines in manpages we need [backslashes in weird places]. Combined with the *, , and `` markup, it's a bit hard to get the alignment right. Fix these by moving synopsis sources back to code blocks and compute HTML syntax highlighting and manpage markup with a custom Sphinx extension. The new Pygments lexer can tokenize a synopsis and assign the various highlighting roles, which closely matches fish's syntax highlighing: - command/keyword (dark blue) - parameter (light blue) - operator like and/or/not/&&/\|\| (cyan) - grammar metacharacter (black) For manpage output, we don't project the fish syntax highlighting but follow the markup convention in GNU's man(1): bold text type exactly as shown. italic text replace with appropriate argument. To make it easy to separate these two automatically, formalize that (italic) placeholders must be uppercase; while all lowercase text is interpreted literally (so rendered bold). This makes manpages more consistent, see string-join(1) and and(1). Implementation notes: Since we want manpage formatting but Sphinx's Pygments highlighing plugin does not support manpage output, add our custom "synopsis" directive. This directive parses differently when manpage output is specified. This means that the HTML and manpage build processes must not share a cache, because the parsed doctrees are cached. Work around this by using separate cache locations for build targets "sphinx-docs" (which creates HTML) and "sphinx-manpages". A better solution would be to only override Sphinx's ManualPageBuilder but that would take a bit more code (ideally we could override ManualPageWriter but Sphinx 4.3.2 doesn't really support that). --- Alternative solution: stick with line blocks but use roles like :command: or :option: (or custom ones). While this would make it possible to produce HTML that is consistent with code blocks (by adding a bit of CSS), the source would look uglier and is harder to maintain. (Let's say we want to add custom formatting to the [\|] metacharacters in HTML. This is much easier with the proposed patch.) --- [RST line blocks]: https://docutils.sourceforge.io/docs/ref/rst/restructuredtext.html#line-blocks [backslashes in weird places]: https://github.com/fish-shell/fish-shell/pull/8626#discussion_r782837750 2022-01-09 15:09:46 +01:00			`.. synopsis::`

			`string trim [-l \| --left] [-r \| --right] [(-c \| --chars) CHARS]`
			`[-q \| --quiet] [STRING ...]`
Add individual documentation pages for string's subcommands This adds string-x.rst for each subcommand x of string. The main page (string.rst) is not changed, except that examples are shown directly after each subcommand. The subcommand sections in string.rst are created by textual inclusion of parts of the string-x.rst files. Subcommand man pages can be viewed with either of: ``` man string collect man string-collect string collect <press F1 or Alt-h> string collect -h ``` While `string -h ...` still prints the full help. Closes #5968 2019-10-27 10:56:24 +01:00
			`.. END SYNOPSIS`

			`Description`
			`-----------`

			`.. BEGIN DESCRIPTION`

docs/string-trim: Double down on the set of chars vs string thing 2024-11-25 17:53:14 +01:00			``string trim`` removes leading and trailing whitespace from each STRING. If -l or --left is given, only leading whitespace is removed. If -r or --right is given, only trailing whitespace is trimmed.

			The -c or --chars switch causes the set of characters in CHARS to be removed instead of whitespace. This is a set of characters, not a string - if you pass ``-c foo``, it will remove any "f" or "o", not just "foo" as a whole.

			`Exit status: 0 if at least one character was trimmed, or 1 otherwise.`
Add individual documentation pages for string's subcommands This adds string-x.rst for each subcommand x of string. The main page (string.rst) is not changed, except that examples are shown directly after each subcommand. The subcommand sections in string.rst are created by textual inclusion of parts of the string-x.rst files. Subcommand man pages can be viewed with either of: ``` man string collect man string-collect string collect <press F1 or Alt-h> string collect -h ``` While `string -h ...` still prints the full help. Closes #5968 2019-10-27 10:56:24 +01:00
			`.. END DESCRIPTION`

			`Examples`
			`--------`

			`.. BEGIN EXAMPLES`

			`::`

			`>_ string trim ' abc '`
			`abc`

			`>_ string trim --right --chars=yz xyzzy zany`
			`x`
			`zan`


			`.. END EXAMPLES`