How to delete Seq[String] from JsObject?

Question

private def updateData(
  oldData: Seq[Data], 
  authorised: Boolean, 
  removeItemList: Seq[String]
): Seq[Data] = {
    if (!authorised) {
      oldData.map { data =>
        val props: Option[JsObject] = data.props.map { 
          props => props.as[JsObject] - removeItemList(0) - removeItemList(1) - removeItemList(2) 
        }
        data.copy(props = props)
      }
    } else {
      oldData
    }
  }

Can we improve this code? so it's work with removeItemList length > 3.

There is a lot of irrelevant code here (e.g. `authorised` test), and some of the types are not defined. It would really help if you just showed the actual operation you are trying to perform as a simple function including the relevant types. — Tim, Jul 29 '20 at 07:15

score 3 · Accepted Answer · answered Jul 29 '20 at 14:02

The trick is to, for every item in removeItemList, remove it from the JsObject which resulted from the last removal.

This is the very definition of a fold:

removeItemList.foldLeft(props.as[JsObject]) { (jso, v) => jso - v }

we use props.as[JsObject] as the start value
for every item in removeItemList, we combine it with the current value with the combining function
the combining function removes the item from the current value

How to delete Seq[String] from JsObject?

1 Answers1