YAML formatter

    Validate and re-indent a YAML document.

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    About the yaml formatter

    Validates YAML and re-emits it with consistent indentation, optionally sorting keys so two files become directly comparable. Multi-document files separated by --- are handled as a set, and a syntax error reports the position that broke parsing rather than failing silently.

    Frequently asked questions

    Why is my indentation rejected?

    YAML forbids tabs for indentation — only spaces. A stray tab from an editor with the wrong settings is the most common cause of an unhelpful parse error.

    Why did my version number become a number?

    Unquoted 1.10 parses as a float and loses the trailing zero. Quote version strings, and quote yes, no, on and off unless you really do mean booleans.

    Often used alongside