xo - Man Page
emit formatted output based on format string and arguments
Examples (TL;DR)
Lint files in the "src" directory:
xo
Lint a given set of files:
xo path/to/file1.js path/to/file2.js ...
Automatically fix any lint issues found:
xo --fix
Lint using spaces as indentation instead of tabs:
xo --space
Lint using the "prettier" code style:
xo --prettier
Synopsis
xo | [-options ] [argument...] |
Description
The xo utility allows command line access to the functionality of the libxo library. Using xo, shell scripts can emit XML, JSON, or HTML using the same commands that emit text output.
- --close path
Close tags for the given path
- -C | --continuation
Indicates this output is a continuation of the previous output data and should appear on the same line. This is allows HTML output to be constructed correctly.
- --depth num
Set the depth for pretty printing
- --help
Display help text
- -H | --html
Generate HTML output
- -J | --json
Generate JSON output
- --leading-xpath path
Add a prefix to generated XPaths (HTML)
- --not-first
Indicate that this content is not the first in a series of sibling objects, which is vital information for "JSON" output, which requires a comma between such objects.
- --open path
Open tags for the given path
- -p | --pretty
Make 'pretty' output (add indent, newlines)
- --style style
Generate given style (xml, json, text, html)
- -T | --text
Generate text output (the default style)
- --top-warp
Indicates the entire object should be placed inside a top-level object wrapper, specifically when generating JSON output.
- --version
Display version information
- -W | --warn
Display warnings in text on stderr
- --warn-xml
Display warnings in xml on stdout
- --wrap path
Wrap output in a set of containers
- -X | --xml
Generate XML output
- --xpath
Add XPath data to HTML output
The xo utility accepts a format string suitable for xo_emit(3) and a set of zero or more arguments used to supply data for that string.
In addition, xo accepts any of the libxo options listed in xo_options(7).
Examples
In this example, xo is used to emit the same data encoded in text and then in XML by adding the "-p" (pretty) and "-X" (XML output) flags:
% xo 'The {:product} is {:status}\n' stereo "in route" The stereo is in route % xo -p -X 'The {:product} is {:status}\n' stereo "in route" <product>stereo</product> <status>in route</status>
In this example, the output from a xo command is shown in several styles:
xo "The {k:name} weighs {:weight/%d} pounds.\n" fish 6 TEXT: The fish weighs 6 pounds. XML: <name>fish</name> <weight>6</weight> JSON: "name": "fish", "weight": 6 HTML: <div class="line"> <div class="text">The </div> <div class="data" data-tag="name">fish</div> <div class="text"> weighs </div> <div class="data" data-tag="weight">6</div> <div class="text"> pounds.</div> </div>
The --wrap <path> option can be used to wrap emitted content in a specific hierarchy. The path is a set of hierarchical names separated by the '/' character.
xo --wrap top/a/b/c '{:tag}' value XML: <top> <a> <b> <c> <tag>value</tag> </c> </b> </a> </top> JSON: "top": { "a": { "b": { "c": { "tag": "value" } } } }
The --open <path> and --close <path> can be used to emit hierarchical information without the matching close and open tag. This allows a shell script to emit open tags, data, and then close tags. The --depth option may be used to set the depth for indentation. The --leading-xpath may be used to prepend data to the XPath values used for HTML output style.
#!/bin/sh xo --open top/data xo --depth 2 '{:tag}' value xo --close top/data XML: <top> <data> <tag>value</tag> </data> </top> JSON: "top": { "data": { "tag": "value" } }
See Also
History
The libxo library first appeared in FreeBSD 11.0.
Authors
libxo was written by Phil Shafer <phil@freebsd.org>.
Additional Documentation
FreeBSD uses libxo version 1.6.0. Complete documentation can be found on github:
https://juniper.github.io/libxo/1.6.0/html/index.html
libxo lives on github as:
https://github.com/Juniper/libxo
The latest release of libxo is available at:
https://github.com/Juniper/libxo/releases
History
The libxo library was added in FreeBSD 11.0.
Author
Phil Shafer