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At first it looked interesting, but as pointed out by other people, it's enough to have a 'partial' json with the field that need update. The syntax stays the same, just add what you want to update. We do exactly that and it's very easy

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The advantage is in mutating arrays. You don't need to send the entire array back, just the commands for which index gets added/ removed / replaced.

Also, there's no way to differentiate between deleting a key from an object and leaving it unchanged if you send a partial patch, assuming that `null` is a distinct value different than actually deleting the key itself.

To your second point, the JSON spec allows `null` but not `undefined`, so most js serializers (all?) don't send (or throw an exception) for any `undefined` from any object you attempt to send. To delete a property, you would send the entire surrounding object. Or you can simply define your data-layer without transient key/values. It's certainly not a necessary feature to have.

How do you delete fields? What about complex documents with dozens of nested fields?

For really simple use cases you don't need this but I've used something similar for an application where the JSON documents could get in the megabytes and it was a lifesaver.

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