return Pair[L, R]{L: l, R: r}
}

type Map[K, V any] interface {
	Put(K, V)
	Len() int
	Iterate(func(Pair[K, V]) bool)
}

type HashMap[K comparable, V any] struct {
	m map[K]V
}

func NewHashMap[K comparable, V any](capacity int) HashMap[K, V] {
	var m map[K]V
	if capacity >= 1 {
		m = make(map[K]V, capacity)
	} else {
		m = map[K]V{}
	}

	return HashMap[K, V]{m: m}
}

// format when given a pointer to a map[string]any.
func Example_parsing() {
	var buf bytes.Buffer
	h := slog.NewJSONHandler(&buf, nil)

	results := func() []map[string]any {
		var ms []map[string]any
		for _, line := range bytes.Split(buf.Bytes(), []byte{'\n'}) {
			if len(line) == 0 {
				continue
			}
			var m map[string]any
			if err := json.Unmarshal(line, &m); err != nil {

//
// missingkey: Control the behavior during execution if a map is
// indexed with a key that is not present in the map.
//
//	"missingkey=default" or "missingkey=invalid"
//		The default behavior: Do nothing and continue execution.
//		If printed, the result of the index operation is the string
//		"<no value>".
//	"missingkey=zero"
//		The operation returns the zero value for the map type's element.
//	"missingkey=error"

	x[2] = 'b'
	return x[3]
}

// Can index an argument (read/write) constrained to be a map. Maps can't
// be combined with any other type for indexing purposes.
func Index3[T interface{ map[int]int64 }](x T) int64 {
	x[2] = 43
	return x[3]
}

// But the type of the map keys or values can be parameterized.
func Index4[T any](x map[int]T) T {
	var zero T
	x[2] = zero
	return x[3]
}

			toInsertWeak = weak.Make(toInsert)
		}
		return toInsertWeak
	}
	var ptr *T
	for {
		// Check the map.
		wp, ok := m.Load(value)
		if !ok {
			// Try to insert a new value into the map.
			wp, _ = m.LoadOrStore(value, newValue())
		}
		// Now that we're sure there's a value in the map, let's
		// try to get the pointer we need out of it.
		ptr = wp.Strong()
		if ptr != nil {
			break
		}

// during constraint type inference.
func f4[M4 map[K4]int, K4 comparable](m4 M4) {}

func f5[M5 map[K5]int, K5 comparable](m5 M5) {
	f4(m5)
}

// test case from issue

func Copy[MC ~map[KC]VC, KC comparable, VC any](dst, src MC) {
	for k, v := range src {
		dst[k] = v
	}
}

func Merge[MM ~map[KM]VM, KM comparable, VM any](ms ...MM) MM {
	result := MM{}
	for _, m := range ms {
		Copy(result, m)
	}
	return result

}

func (m *DeepCopyMap) Range(f func(key, value any) (shouldContinue bool)) {
	clean, _ := m.clean.Load().(map[any]any)
	for k, v := range clean {
		if !f(k, v) {
			break
		}
	}
}

func (m *DeepCopyMap) dirty() map[any]any {
	clean, _ := m.clean.Load().(map[any]any)
	dirty := make(map[any]any, len(clean)+1)
	for k, v := range clean {
		dirty[k] = v
	}
	return dirty
}

// Test type-checking errors for go:notinheap.

package p

//go:notinheap
type nih struct{}

type embed4 map[nih]int // ERROR "incomplete \(or unallocatable\) map key not allowed"

type embed5 map[int]nih // ERROR "incomplete \(or unallocatable\) map value not allowed"

type emebd6 chan nih // ERROR "chan of incomplete \(or unallocatable\) type not allowed"

type okay1 *nih

type okay2 []nih

	testcases := []struct {
		vars      []*ir.Name
		partition map[*ir.Name][]int
		experr    bool
	}{
		{
			vars: []*ir.Name{v1, v2, v3},
			partition: map[*ir.Name][]int{
				v1: []int{0, 1, 2},
				v2: []int{0, 1, 2},
				v3: []int{0, 1, 2},
			},
			experr: false,
		},
		{
			// invalid mls.v slot -1
			vars: []*ir.Name{v1, v2, v3},
			partition: map[*ir.Name][]int{
				v1: []int{-1, 0},
				v2: []int{0, 1, 2},

	checkOpcodeCounts(t, fun.f, map[Op]int{OpAMD64SHLQconst: 1, OpAMD64CMPQconst: 0, OpAMD64ANDQconst: 0})

	fun = makeConstShiftFunc(c, 66, OpLsh64x64, c.config.Types.UInt64)
	checkOpcodeCounts(t, fun.f, map[Op]int{OpAMD64SHLQconst: 0, OpAMD64CMPQconst: 0, OpAMD64ANDQconst: 0})

	fun = makeConstShiftFunc(c, 18, OpRsh64Ux64, c.config.Types.UInt64)