Dataweave remove empty array

Question

We are running MuleEsb 3.9.0 I'm trying to remove empty array's in my dataweave transformation. For example:

payload map ((value , indexOfValue) -> {
 value : {
    content: value.content,
    subvalue: value.subValue map ((subValue, indexOfsubValue)->
    {
        sub: subValue
    }) filter ($.sub != null )
  }
})

this will result in

[
  {
    value:
     {
       content: xyz
       subValue: []
     }
  }
]

i want subValue to be totally removed. to be outputted:

[
  {
    value:
     {
       content: xyz
     }
  }
]

Answer 1

You need something like this:

payload map ((v) -> {
  value: {
    content: v.content,
    (subvalue: v.subValue map ... ) when ((sizeOf v.subValue) != 0)
  }
})