default:
		return 0, fmt.Errorf("cannot index slice/array with type %s", index.Type())
	}
	if x < 0 || int(x) < 0 || int(x) > cap {
		return 0, fmt.Errorf("index out of range: %d", x)
	}
	return int(x), nil
}

// Indexing.

// index returns the result of indexing its first argument by the following
// arguments. Thus "index x 1 2 3" is, in Go syntax, x[1][2][3]. Each

			resources:    testResources([]resourceapi.NamedResourcesInstance{{Name: goodName, Attributes: []resourceapi.NamedResourcesAttribute{{Name: goodName}}}}),
		},
		"duplicate-value": {

	// Start writing `xl.meta` to all disks in parallel.
	for index := range disks {
		index := index
		g.Go(func() error {
			if disks[index] == nil {
				return errDiskNotFound
			}
			// Pick one FileInfo for a disk at index.
			fi := files[index]
			fi.Erasure.Index = index + 1
			if fi.IsValid() {
				return disks[index].WriteMetadata(ctx, origbucket, bucket, prefix, fi)
			}
			return errFileCorrupt

	p.x, p.y, p.z = t0.x, t0.y, p256One
	p256NegCond(&p.y, sign)

	index := uint(5)
	zero := sel

	for i := 1; i < 43; i++ {
		if index < 192 {
			wvalue = ((scalar[index/64] >> (index % 64)) + (scalar[index/64+1] << (64 - (index % 64)))) & 0x7f
		} else {
			wvalue = (scalar[index/64] >> (index % 64)) & 0x7f
		}
		index += 6
		sel, sign = boothW6(uint(wvalue))

		// if priority of pod is:
		//   groups[index-1].Priority <= pod priority < groups[index].Priority
		// in which case we want to pick lower one (i.e index-1)
		if index == len(groups) {
			index = len(groups) - 1
		} else if index < 0 {
			index = 0
		} else if index > 0 && groups[index].Priority > priority {
			index--
		}

		groups[index].Pods = append(groups[index].Pods, pod)
	}
	return groups
}

// other language matched.
func MatchStrings(m Matcher, lang ...string) (tag Tag, index int) {
	for _, accept := range lang {
		desired, _, err := ParseAcceptLanguage(accept)
		if err != nil {
			continue
		}
		if tag, index, conf := m.Match(desired...); conf != No {
			return tag, index
		}
	}
	tag, index, _ = m.Match()
	return
}

// Matcher is the interface that wraps the Match method.
//

	spineLen  atomic.Uintptr            // Spine array length
	spineCap  uintptr                   // Spine array cap, accessed under spineLock

	// index is the head and tail of the spanSet in a single field.
	// The head and the tail both represent an index into the logical
	// concatenation of all blocks, with the head always behind or
	// equal to the tail (indicating an empty set). This field is
	// always accessed atomically.

	// bytes into em.
	validPS := subtle.ConstantTimeLessOrEq(2+8, index)

	valid = firstByteIsZero & secondByteIsTwo & (^lookingForIndex & 1) & validPS
	index = subtle.ConstantTimeSelect(valid, index+1, 0)
	return valid, em, index, nil
}

// nonZeroRandomBytes fills the given slice with non-zero random octets.
func nonZeroRandomBytes(s []byte, random io.Reader) (err error) {

	g := errgroup.WithNErrs(len(storageDisks))

	// Write `format.json` to all disks.
	for index := range storageDisks {
		index := index
		g.Go(func() error {
			if formats[index] == nil {
				return errDiskNotFound
			}
			return saveFormatErasure(storageDisks[index], formats[index], "")
		}, index)
	}

	// Wait for the routines to finish.

	n := e.From()
	index := g.destinationEdgeIndex[n.ID()]
	if index == nil {
		// There is no index, use the full index computation method
		g.recomputeDestinationIndex_locked(n)
		return
	}
	// fast-add the new edge to an existing index
	if destinationEdge, ok := e.(*destinationEdge); ok {
		index.increment(destinationEdge.DestinationID())
	}
}