{
"headers": [ "a", "b", "c" ],
"rows": [
[ 1, 2, 3 ],
[ 4, 5, 6 ],
]
}
Also, in the table it claims "Yes" under support for "Cyclic references", and yet further down the page:
> ION has support for expressing cyclic references between objects. At this point this support is not 100% finalized.
So surely this should be "Yes(*)"?
Second, an array of arrays could mean anything. You have not semantics telling whether the arrays are independent or if the first array is an array of columns for the following arrays. ION Tables add that semantic information.
Third, yes, we could encode everything as text or as raw bytes and leave it up to the user to make sense of it. But that is exactly what we are trying to avoid with ION. We want to give devs a decent standard data format to use, that doesn't require a lot of data encoding choices up front. The encoding options have been thought through already, and sensible choices already made which you can just follow.
Fourth, you can nest ION tables inside ION tables, and thus create a more compact representation of an object graph. Using JSON / CBOR you would need a lot of nested arrays inside arrays to emulate that. Possible, but not exactly pretty.
Additionally, if a message does not include its length up front, you are just trading faster write time for slower read time. A node receiving dynamically sized data then has the problem of knowing how much data to allocate for the full message, plus the receiver has to inspect the data as it comes in to see where it ends. With an ION message the receiver knows within the first 4-5 bytes (typically) how big that message will be, and can thus copy the following bytes directly into the perfectly allocated memory area, without having to examine them any further. Since data is most often read more times than written (e.g. data written to a file), we felt that making a tradeoff that favors read speed over write speed made sense.
http://tutorials.jenkov.com/iap/ion-vs-other-formats.html
Not every innovation is from scratch, or 100% unique. MessagePack was designed as a binary encoding of JSON. CBOR too. ION was designed to be a binary general purpose data format able to mimic both JSON, XML, CSV and raw bytes (files), plus the most commonly used data types.
Of course there will be similarities when we try to tackle the same problems, but we also believe we had added something new and useful to the mix.
[1] https://tools.ietf.org/html/rfc7049 [2] http://cbor.io/