}
    }
    return tailMap(fromKey);
  }

  private ImmutableSortedMap<K, V> newView(SortedMap<K, V> delegate) {
    return newView(delegate, comparator);
  }

  private static <K, V> ImmutableSortedMap<K, V> newView(
      SortedMap<K, V> delegate, Comparator<? super K> comparator) {
    return new ImmutableSortedMap<K, V>(delegate, comparator);
  }

  /*

	for name, def := range d.known {
		if def.Bounds == nil {
			continue
		}
		// for each histogram metric (i.e. those with bounds), set up a view explicitly defining those buckets.
		v := metric.WithView(metric.NewView(
			metric.Instrument{Name: name},
			metric.Stream{Aggregation: metric.AggregationExplicitBucketHistogram{
				Boundaries: def.Bounds,
			}},
		))
		opts = append(opts, v)
	}
	return opts

			fld := d.newdie(dwhb, dwarf.DW_ABRV_STRUCTFIELD, "keys")
			d.newrefattr(fld, dwarf.DW_AT_type, dwhks)
			newmemberoffsetattr(fld, abi.MapBucketCount)
			fld = d.newdie(dwhb, dwarf.DW_ABRV_STRUCTFIELD, "values")
			d.newrefattr(fld, dwarf.DW_AT_type, dwhvs)
			newmemberoffsetattr(fld, abi.MapBucketCount+abi.MapBucketCount*int32(keysize))
			fld = d.newdie(dwhb, dwarf.DW_ABRV_STRUCTFIELD, "overflow")