cjkfmt-0.0.9 is not a library.

cjkfmt

Installation

Cargo

Install the rust toolchain in order to have cargo installed by following this guide.
run cargo install cjkfmt

Formatting Files

To replace named files with their formatted content, use the --write option:

cjkfmt format --write README.md docs/example.md

Omitting --write leaves the source files unchanged and sends formatted content to stdout.

Language Selection

Named files are classified by their final extension: .md and .markdown select Markdown, and .json selects JSON. Matching is case-insensitive for ASCII letters. For check and debug-cst, other named paths require an explicit --language markdown or --language json. An explicit selection always takes precedence over the filename. format applies Markdown-prose spacing only to Markdown input and, by default, runs the general line-wrapping pass for selected Markdown and JSON input. Unsupported named paths are returned unchanged by format unless an explicit --language override selects a language.

When reading stdin without --language, check and debug-cst assume Markdown. format does not select a language, so it skips both Markdown-prose spacing and line wrapping. Use --language markdown or --language json to select the stdin language explicitly.

Line Wrapping

Line wrapping defaults to split, preserving the existing safe wrapping behavior. Set it to preserve to keep existing physical lines while still applying configured Markdown spacing. This mode does not add, remove, or join line breaks, normalize line endings, or change final-newline presence. JSON has no spacing edits, so it remains byte-identical in preserve mode.

The option is available in JSON configuration, the environment, and the CLI:

{ "line_wrapping": "preserve" }

CJKFMT_LINE_WRAPPING=preserve cjkfmt format --language markdown README.md
cjkfmt --line-wrapping preserve format --language markdown README.md

check reports W001 for overlong physical input lines regardless of this setting or whether a safe wrapping opportunity exists. Formatting does not guarantee that W001 is clear: preserved lines may remain overlong, and spacing edits can make a line exceed max_width.

Exit Status

cjkfmt check exits with status 0 when it completes without diagnostics, status 1 when it completes with one or more diagnostics, and status 2 when checking cannot be completed because of invalid arguments or configuration, input errors, or another operational failure.

Configuration

cjkfmt can be configured in several ways, with configuration options applied in the following order of precedence (highest to lowest):

Command line options
Environment variables prefixed with CJKFMT_
JSON configuration file .cjkfmt.json found in the current or ancestor directories
JSON configuration file .cjkfmt.json in the user's configuration directory (XDG_CONFIG_HOME if set, otherwise $HOME)
Default values

The configuration file is searched for in the current directory and, if not found, in each parent directory up to the root. Only the first file found will be used.

Configuration Options

Currently, the following configuration options are available:

Option	Description	Default
`ambiguous_width`	Width of Unicode Ambiguous characters (`narrow` or `wide`)	`wide`
`line_wrapping`	Preserve lines or split at safe points	`split`
`max_width`	Maximum line width to allow	80
`spacing.alphabets`	Require, prohibit, or ignore spaces around full-/half-width alphabets	`ignore`
`spacing.digits`	Require, prohibit, or ignore spaces around full-/half-width digits	`ignore`

Depending on the configuration source, the option names are formatted slightly differently:

JSON configuration files
- Use underscores between words. Example: max_width
Environment variables
- Write names in ALL CAPITAL LETTERS with underscores between words, and always start with CJKFMT_. Example: CJKFMT_MAX_WIDTH
Command line options
- Use hyphens between words, and put two dashes before the option name. Examples: --max-width 100, --ambiguous-width narrow, --line-wrapping preserve, --spacing-alphabets require, and --spacing-digits prohibit

Example Configuration File

The format command applies the spacing rules to Markdown prose, including visible text inside emphasis and links. Code spans, fenced code blocks, URLs, HTML, and other non-prose inline content are left unchanged. For the implementation-level character classification and the difference between check and format, see the spacing implementation notes.

Below is an example configuration file .cjkfmt.json.

{
  "ambiguous_width": "wide",
  "line_wrapping": "split",
  "max_width": 100,
  "spacing": {
    "alphabets": "require",
    "digits": "ignore"
  }
}

License

Licensed under either of

Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.

See CONTRIBUTING.md.

cjkfmt 0.0.9