}
	if !reflect.DeepEqual(got.NamedEdgeMap.ByWeight, want.NamedEdgeMap.ByWeight) {
		return fmt.Errorf("got.NamedEdgeMap.ByWeight != want.NamedEdgeMap.ByWeight\ngot = %+v\nwant = %+v", got.NamedEdgeMap.ByWeight, want.NamedEdgeMap.ByWeight)
	}
	if !reflect.DeepEqual(got.NamedEdgeMap.Weight, want.NamedEdgeMap.Weight) {

		return NamedEdgeMap{}, 0, nil // accept but ignore profile with no samples.
	}
	byWeight := make([]NamedCallEdge, 0, len(weight))
	for namedEdge := range weight {
		byWeight = append(byWeight, namedEdge)
	}
	sortByWeight(byWeight, weight)

	edgeMap = NamedEdgeMap{
		Weight:   weight,
		ByWeight: byWeight,
	}

	totalWeight = weightVal

	return edgeMap, totalWeight, nil

type ByName struct{ Organs }

func (s ByName) Less(i, j int) bool { return s.Organs[i].Name < s.Organs[j].Name }

// ByWeight implements sort.Interface by providing Less and using the Len and
// Swap methods of the embedded Organs value.
type ByWeight struct{ Organs }

func (s ByWeight) Less(i, j int) bool { return s.Organs[i].Weight < s.Organs[j].Weight }

func Example_sortWrapper() {
	s := []*Organ{
		{"brain", 1340},

type NamedEdgeMap struct {
	Weight map[NamedCallEdge]int64

	// ByWeight lists all keys in Weight, sorted by edge weight from
	// highest to lowest.
	ByWeight []NamedCallEdge
}

func emptyProfile() *Profile {
	// Initialize empty maps/slices for easier use without a requiring a
	// nil check.
	return &Profile{
		NamedEdgeMap: NamedEdgeMap{
			ByWeight: make([]NamedCallEdge, 0),
			Weight:   make(map[NamedCallEdge]int64),
		},

		}

		if _, ok := d.NamedEdgeMap.Weight[edge]; ok {
			return nil, fmt.Errorf("preprocessed profile contains duplicate edge %+v", edge)
		}

		d.NamedEdgeMap.ByWeight = append(d.NamedEdgeMap.ByWeight, edge) // N.B. serialization is ordered.
		d.NamedEdgeMap.Weight[edge] += weight
		d.TotalWeight += weight
	}

	return d, nil

	var written int64

	// Header
	n, err := bw.WriteString(serializationHeader)
	written += int64(n)
	if err != nil {
		return written, err
	}

	for _, edge := range d.NamedEdgeMap.ByWeight {
		weight := d.NamedEdgeMap.Weight[edge]

		n, err = fmt.Fprintln(bw, edge.CallerName)
		written += int64(n)
		if err != nil {
			return written, err
		}

		n, err = fmt.Fprintln(bw, edge.CalleeName)