What valid JSON files are not valid YAML 1.1 files?

Question

YAML 1.2 is (with one minor caveat regarding duplicate keys) a superset of JSON, so any valid JSON file is also a valid YAML file. However, the YAML 1.1 specification (which ha

Answer 1

See here (specifically footnote 25). It says:

The incompatibilities were as follows: JSON allows extended character sets like UTF-32 and had incompatible unicode character escape syntax relative to YAML; YAML required a space after separators like comma, equals, and colon while JSON does not. Some non-standard implementations of JSON extend the grammar to include Javascript's /*...*/ comments. Handling such edge cases may require light pre-processing of the JSON before parsing as in-line YAML

See also https://metacpan.org/pod/JSON::XS#JSON-and-YAML

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