CDN (CBOR-EDN) for Visual Studio Code

Language support for CDN (Concise Diagnostic Notation, draft-ietf-cbor-edn-literals), the human-readable text format for CBOR data and a superset of JSON.

Powered by @cbortech/cbor, so highlighting, validation, and formatting agree exactly with a real CDN parser. A live playground for the library is available at https://cbor.tech/cbor/.

CDN syntax highlighting in Visual Studio Code

Features

Syntax highlighting for .cdn, .diag, and .edn files: numbers in all bases, hex floats, text/byte strings (h'…', b64'…', '…', `…`), application-oriented literals (dt'…', ip'…', …), tags, embedded CBOR (<< … >>), encoding indicators (_, _3), ellipsis (...), and all four comment styles (#, //, /* … */, / … /).
Validation as you type: syntax errors and CDN validity violations are underlined at their exact source range.
Application extensions: all bundled @cbortech/cbor extensions (dt, ip, cri, t1, b1, ilbs, ilts, float, same, b32, h32) plus hash'…' (@cbortech/hash-extension), uuid'…' (@cbortech/uuid-extension), and SET<<…>> / MAP<<…>> (@cbortech/set-map-extensions) are recognized and validated out of the box. Each one can be disabled individually via cdn.extensions.* for allowlisting scenarios.
Formatting (Format Document): pretty-prints with your editor's indentation settings while preserving comments and the original spelling of byte strings. The formatter verifies that the formatted text still parses to the same data before touching your document, and does nothing otherwise.

Settings

Setting	Default	Description
`cdn.validate.enable`	`true`	Enable validation.
`cdn.validate.topLevel`	`"item"`	`"item"`: one CDN data item per document (application/cdn). `"sequence"`: allow multiple items (CBOR sequence). Also controls the formatter.
`cdn.format.commas`	`"comma"`	Comma style: `comma`, `none`, or `trailing`.
`cdn.format.comments`	`"preserve"`	Keep comments as-is, normalize to `c-style` / `cdn-style`, or `strip`.
`cdn.format.encodingIndicators`	`"auto"`	Emit `_N` indicators `always`, `auto` (only when non-canonical), or `never`.
`cdn.format.appPrefix`	`true`	Prefer `dt'…'`-style app-prefix literals over raw tag notation.
`cdn.format.bstrEncoding`	`"hex"`	Fallback byte-string encoding: `hex`, `base64`, `base64url`.
`cdn.format.preserveByteString`	`true`	Keep the original spelling of byte-string literals.
`cdn.format.preserveRawString`	`true`	Keep the original spelling of raw backtick string literals (`…`).
`cdn.format.preserveNumberFormat`	`true`	Keep the original spelling of integer and floating-point literals.
`cdn.format.preserveAppPrefix`	`true`	Keep the original notation (e.g. `dt'…'` vs `DT<<…>>` vs raw tag) of extension app-prefix literals.
`cdn.format.preserveBlankLines`	`true`	Re-emit a blank line above an array/map entry that had one in the source.
`cdn.format.preserveConcatenation`	`true`	Keep `+` concatenation chains (`"a" + "b"`) from the source.
`cdn.format.splitCdn`	`true`	Split text strings whose content parses as CDN, with structure-aware indentation.
`cdn.format.splitNewline`	`true`	Split text strings at newline characters using `+` concatenation.
`cdn.format.inlineLeafContainers`	`true`	Keep arrays/maps with no nested containers on a single line (e.g. `[1, 2, 3]`).
`cdn.format.floatFormat`	unset	Numeric format for floats: `decimal`, `hex`, or `app-extension` (`float'…'`, lossless for NaN/±Infinity). Only takes effect where the original spelling isn't otherwise kept: for a plain float literal, combine with `preserveNumberFormat: false`; for a `float'…'` literal, leave unset to keep its bit-pattern spelling — `decimal`/`hex` renormalize it and can lose a NaN payload.
`cdn.format.modernConcat`	`false`	Render `+` concatenation / elision chains as `t1<<…>>` / `b1<<…>>` app-sequence notation.
`cdn.format.modernStreamSyntax`	`false`	Render indefinite-length strings as `ilts<<…>>` / `ilbs<<…>>` app-sequence notation instead of `(_ "a", "b")`.
`cdn.extensions.<name>`	`true`	Enable/disable each application extension individually: `dt`, `ip`, `cri`, `t1`, `b1`, `ilbs`, `ilts`, `float`, `same`, `b32`, `h32`, `hash`, `uuid`, `set`, `map`. Disabled prefixes are reported with a hint and parsed as unresolved (tag 999).

Note: dt, ip, t1, and b1 are mandatory-to-implement per draft-ietf-cbor-edn-literals-27 §3; disabling them makes validation stricter than the spec recommends.

License

Apache-2.0