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Comment by TedDoesntTalk | Hacker News Reader

How is YAML a superset of JSON? never heard that claim before.

You can turn any piece of a YAML into a JSON object and it will be read just as well.

This YAML:

    user:
      name: Ted

is equivalent to this YAML:

    user: {"name": "Ted"}

which is equivalent to this YAML/JSON:

    {"user": {"name": "Ted"}}

While true, this is what being a supperset means. What it means is that any JSON document is, without modification, valid YAML document and can be read with a YAML parser.

That's exactly the case. Any YAML 1.2 parser can parse any valid json document as is.

I think you mean "this isn't what".

YAML supports tagged nodes and multiple documents in a stream, which can’t be represented in standard JSON. (You could make up conventions, but only your parser would support them.)

It just is: Any valid JSON is valid YAML with the same semantics. It was intentionally designed that way (though not from the start iirc).

Basically take JSON, make quotes optional for strings and make curly brackets optional if the object is indented properly, and boom you've got (something like) YAML.

If all JSON is YAML but not all YAML is JSON, then YAML is a superset of JSON.

Any valid json can be parsed by any 1.2 yaml parser. That's how it gained popularity in the first place: you didn't have to migrate. Like ascii and utf8.

When YAML came out there was no large JSON usage to migrate from, the incumbent in configuration was "human readable serialization" was XML.

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