       splitName = condensedCommand.split.name
       if sortApplySegmentation.length is 0
         # Sorting on splitting prop
-        throw new Error("not implemented yet")
+        throw new Error("prop split not implemented yet")
       else if sortApplySegmentation.length is 1
         # Sorting on regular apply
         mainDataset = sortApplySegmentation[0].dataset



class ApplySegregator
  constructor: () ->
    @byDataset = {}
    @postProcess = []
    @nameIndex = 0

      drivenQueries = driverUtil.filterMap perDatasetInfo, (info) ->
        return unless info.driven

        throw new Error("This (#{condensedCommand.split.bucket}) split not implemented yet") unless info.condensedCommand.split.bucket is 'identity'
        driverFilter = new InFilter({
          attribute: info.condensedCommand.split.attribute
          values: driverResult.map((prop) -> prop[splitName])
