strange behaviour when processing sparse arrays

[janvda]

The problem is also raised in node-red forum :

• Weird behaviour when processing an array of arrays having null values

So as input we are using the following sparse array:

Although the above screenshot shows payload[1][1] = null - actually this array element is not specified in javascript (= sparse javascript array).

When running the following script:

payload.{
   "row" : $
}

then the "null" cell gets removed as you can see in below output:

Is this expected behaviour ?

[andrew-coleman]

I see there is a lot more discussion on the node-red forum, but from a pure jsonata point of view, I would be interested to know what the input JSON data looks like.

The entire JSONata test suite is specified as JSON in / JSON out to make it implementation agnostic (there was once a Go implementation - not sure what became of it).

There is no defined behaviour for inputs that can't be expressed in JSON, and I don't think sparse arrays can be.

[janvda]

With node-red it is possible to pass a sparse array as input for a JSONata expression in a change node.

I agree that sparse arrays can't be expressed in JSON.
I also agree that in that case the behavior is undefined.

So for me it is fine to close this issue.