Converting a map of objects to an array of CDTs

I'm currently doing the following:

a!save(
  target: local!SelectedRows,
  value: save!value
),
a!save(
  target: local!SelectedSites,
  value: append(local!SelectedSites, fv!selectedRows)
),
a!save(
  target: local!SelectedSites,
  value: difference(local!SelectedSites, fv!deselectedRows)
),
a!save(
  target: ri!SelectedSites,
  value: a!forEach(
    items: local!SelectedSites,
    expression: cast('type!Site', fv!item)
  )
)

I'm currently doing the following:

a!save(
  target: local!SelectedRows,
  value: save!value
),
a!save(
  target: local!SelectedSites,
  value: append(local!SelectedSites, fv!selectedRows)
),
a!save(
  target: local!SelectedSites,
  value: difference(local!SelectedSites, fv!deselectedRows)
),
a!save(
  target: ri!SelectedSites,
  value: a!forEach(
    items: local!SelectedSites,
    expression: cast('type!Site', fv!item)
  )
)

That should work, but you can also eliminate one of the saves if you directly cast the data in your append and difference functions above like this:

selectionSaveInto: {
  local!selection,
  a!save(
    ri!case, append(
      ri!case, cast(
        'type!{urn:com:appian:types:PDL}PDL_Client?list',
        fv!selectedRows
      )
    )
  ),
  a!save(
    ri!case, 
    difference(
      ri!case, 
      cast(
        'type!{urn:com:appian:types:PDL}PDL_Client?list',
        fv!deselectedRows
      )
    )
  )
}