JSON is simplified subset of JavaScript data syntax.
Adding a few more JS features to JSON would help usability.
The JSON5 Data Interchange Format (json5.org)
"The JSON5 Data Interchange Format (JSON5) is a superset of JSON that aims to alleviate some of the limitations of JSON by expanding its syntax to include some productions from ECMAScript 5.1.Similar to JSON, JSON5 can represent four primitive types (strings, numbers, Booleans, and null) and two structured types (objects and arrays)."
example:
{ // comments unquoted: 'and you can quote me on that', singleQuotes: 'I can use "double quotes" here', lineBreaks: "Look, Mom! \ No \\n's!", hexadecimal: 0xdecaf, leadingDecimalPoint: .8675309, andTrailing: 8675309., positiveSign: +1, trailingComma: 'in objects', andIn: ['arrays',], "backwardsCompatible": "with JSON", }
GitHub Search · json5
json vs json5 vs yaml | npm trends (json5 = 3 * yaml)
there are also official "readonly" versions in DotNet (C#) and GoLang (go) JSON5 @github
Rust
ANTLR parser grammar for JSON5
