use121 = true
		httpmuxgo121.IncNonDefault()
	}
}

// serveMux121 holds the state of a ServeMux needed for Go 1.21 behavior.
type serveMux121 struct {
	mu    sync.RWMutex
	m     map[string]muxEntry
	es    []muxEntry // slice of entries sorted from longest to shortest.
	hosts bool       // whether any patterns contain hostnames
}

type muxEntry struct {
	h       Handler
	pattern string
}

//
// File system operations read directly from the map,
// so that the file system can be changed by editing the map as needed.
// An implication is that file system operations must not run concurrently
// with changes to the map, which would be a race.
// Another implication is that opening or reading a directory requires
// iterating over the entire map, so a MapFS should typically be used with not more

// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package p

type Message struct {
	Header map[string][]string
}

func f() {
	m := Message{Header: map[string][]string{}}
	m.Header[""] = append([]string(m.Header[""]), "")
	_ = m

func NewInheritanceMatcher(t []language.Tag) *InheritanceMatcher {
	tags := &InheritanceMatcher{make(map[language.Tag]int)}
	for i, tag := range t {
		ct, err := language.All.Canonicalize(tag)
		if err != nil {
			ct = tag
		}
		tags.index[ct] = i
	}
	return tags
}

type InheritanceMatcher struct {
	index map[language.Tag]int
}

var kvFuncs = map[string]map[string]int{
	"": map[string]int{
		"Debug":        1,
		"Info":         1,
		"Warn":         1,
		"Error":        1,
		"DebugContext": 2,
		"InfoContext":  2,
		"WarnContext":  2,
		"ErrorContext": 2,
		"Log":          3,
		"Group":        1,
	},
	"Logger": map[string]int{
		"Debug":        1,
		"Info":         1,

//go:build darwin || dragonfly || freebsd || netbsd || openbsd

package route

import (
	"syscall"
	"unsafe"
)

var (
	nativeEndian binaryByteOrder
	kernelAlign  int
	rtmVersion   byte
	wireFormats  map[int]*wireFormat
)

func init() {
	i := uint32(1)
	b := (*[4]byte)(unsafe.Pointer(&i))
	if b[0] == 1 {
		nativeEndian = littleEndian
	} else {
		nativeEndian = bigEndian
	}

// as an ordered list of edges. If there are multiple shortest paths,
// which one is returned is unpredictable.
func (g *_Graph[_Node, _Edge]) ShortestPath(from, to _Node) ([]_Edge, error) {
	visited := make(map[_Node]bool)
	visited[from] = true
	workqueue := []nodePath[_Node, _Edge]{nodePath[_Node, _Edge]{from, nil}}
	for len(workqueue) > 0 {
		current := workqueue
		workqueue = nil
		for _, np := range current {

package dag

import (
	"cmp"
	"fmt"
	"slices"
	"strings"
)

type Graph struct {
	Nodes   []string
	byLabel map[string]int
	edges   map[string]map[string]bool
}

func newGraph() *Graph {
	return &Graph{byLabel: map[string]int{}, edges: map[string]map[string]bool{}}
}

func (g *Graph) addNode(label string) bool {
	if _, ok := g.byLabel[label]; ok {
		return false
	}

		Period:     1,
		SampleType: []*profile.ValueType{
			{Type: "contentions", Unit: "count"},
			{Type: "delay", Unit: "nanoseconds"},
		},
	}
	locs := make(map[uint64]*profile.Location)
	funcs := make(map[string]*profile.Function)
	for _, rec := range prof {
		var sloc []*profile.Location
		for _, frame := range rec.Stack {
			loc := locs[frame.PC]
			if loc == nil {

	for _, c := range calls {
		v, ok := c.apply(m)
		results = append(results, mapResult{v, ok})
	}

	final = make(map[any]any)
	m.Range(func(k, v any) bool {
		final[k] = v
		return true
	})

	return results, final
}

func applyMap(calls []mapCall) ([]mapResult, map[any]any) {
	return applyCalls(new(sync.Map), calls)
}