anchor.diff:  --------------------------------------------------
   // NOTCONSOLE
   
  -==== Empty Buckets
  +[[scripted-metric-aggregation-empty-buckets]]
  +==== Empty buckets
   
   If a parent bucket of the scripted metric aggregation does not collect any documents an empty aggregation response will be returned from the
   shard with a `null` value. In this case the `reduce_script`'s `states` variable will contain `null` as a response from that shard.
  
positive.code: --------------------------------------------------
  // NOTCONSOLE
  
  ==== Other Parameters
  
  [horizontal]
  params::           Optional. An object whose contents will be passed as variables to the  `init_script`, `map_script` and `combine_script`. This can be
  
negative.code: * Map (containing only keys and values of the types listed here)
  * Array (containing elements of only the types listed here)
  
  [[scripted-metric-aggregation-scope]]
  ==== Scope of scripts
  
  The scripted metric aggregation uses scripts at 4 stages of its execution:
  