Path Operator on empty array returns *no data* which doesn't work nicely with boolean function

[vuquocbao]

Hello,

I'm running into an issue where performing a . operator on an empty array returns no data.

Example:
Lets say I have a json like this

{
   "myList": []
}

If I do an expression like this $boolean(myList) I get false.

But if I do something like this $boolean(myList.someVar) I get undefined.

This causes some problems because lets say the list contains a JsonObject. The second expression only works if there is at least one object in the list.

Note that if I use the $count function instead of the boolean it will always return 0.

I also encounter this problem when filtering.

So if I do something like this myList[type = 'SomeType']. If the list is empty that returns undefined or no data in the online editor. If there is at least one item that matches the filter it gets returns. If there is no items that matches it returns undefined.

But I think the biggest problem is how $boolean does work for undefined results like javascript. Ideally calling $boolean should return false if the filtering or path operation on the array results in undefined

[markmelville]

Are you aware of the $exists function? It will return false when there is no match. docs. The same page has the docs for $boolean as well. If would be good if the docs said that no match will return no match, and that the $exists function could be used first/instead.