Does JSON syntax allow duplicate keys in an object?

Question

Is this valid json?

{
    \"a\" : \"x\",
    \"a\" : \"y\"
}

http://jsonlint.com/ says yes.

http://www.json.org/ doesn\'t say anyth

Answer 1

There are 2 documents specifying the JSON format:

1. http://json.org/
2. https://tools.ietf.org/html/rfc7159

The accepted answer quotes from the 1st document. I think the 1st document is more clear, but the 2nd contains more detail.

The 2nd document says:

4. Objects

   An object structure is represented as a pair of curly brackets surrounding zero or more name/value pairs (or members). A name is a string. A single colon comes after each name, separating the name from the value. A single comma separates a value from a following name. The names within an object SHOULD be unique.

So it is not forbidden to have a duplicate name, but it is discouraged.