"math"
	"math/bits"
)

// Mask allows filtering by a bitset mask.
type Mask uint64

const (
	// MaskAll is the mask for all entries.
	MaskAll Mask = math.MaxUint64
)

// MaskFromMaskable extracts mask from an interface.
func MaskFromMaskable(m Maskable) Mask {
	return Mask(m.Mask())
}

// Contains returns whether *all* flags in other is present in t.
func (t Mask) Contains(other Mask) bool {
	return t&other == other

	sub := &Sub[T]{ch: subCh, types: Mask(mask.Mask()), filter: filter}
	ps.subs = append(ps.subs, sub)

	// We hold a lock, so we are safe to update
	combined := Mask(atomic.LoadUint64(&ps.types))
	combined.Merge(Mask(mask.Mask()))
	atomic.StoreUint64(&ps.types, uint64(combined))

	go func() {
		<-doneCh

		ps.Lock()
		defer ps.Unlock()
		var remainTypes Mask
		for i, s := range ps.subs {
			if s == sub {

  static int getHashPrefix(int value, int mask) {
    return value & ~mask;
  }

  /** Returns the index, or 0 if the entry is "null". */
  static int getNext(int entry, int mask) {
    return entry & mask;
  }

  /** Returns a new value combining the prefix and suffix using the given mask. */
  static int maskCombine(int prefix, int suffix, int mask) {
    return (prefix & ~mask) | (suffix & mask);
  }

  static int remove(

    int hash = smearedHash(object);
    int mask = hashTableMask();
    int tableIndex = hash & mask;
    int next = CompactHashing.tableGet(requireTable(), tableIndex);
    if (next == UNSET) { // uninitialized bucket
      if (newSize > mask) {
        // Resize and add new entry
        mask = resizeTable(mask, CompactHashing.newCapacity(mask), hash, newEntryIndex);
      } else {

    TYPE_DISALLOWED -> TYPE_DISALLOWED

    else -> error("unexpected type: $type")
  }
}

internal infix fun Byte.and(mask: Int): Int = toInt() and mask

internal infix fun Short.and(mask: Int): Int = toInt() and mask

  public void setUp() {
    int tableSize = ImmutableSet.chooseTableSize(size);
    int mask = tableSize - 1;
    for (int i = 0; i < TEST_CASES; i++) {
      tables[i] = new Object[tableSize];
      for (int j = 0; j < size; j++) {
        Object o = new Object();
        for (int k = o.hashCode(); ; k++) {
          int index = k & mask;
          if (tables[i][index] == null) {
            tables[i][index] = o;
            break;

  static int getHashPrefix(int value, int mask) {
    return value & ~mask;
  }

  /** Returns the index, or 0 if the entry is "null". */
  static int getNext(int entry, int mask) {
    return entry & mask;
  }

  /** Returns a new value combining the prefix and suffix using the given mask. */
  static int maskCombine(int prefix, int suffix, int mask) {
    return (prefix & ~mask) | (suffix & mask);
  }

  static int remove(

    int hash = smearedHash(object);
    int mask = hashTableMask();
    int tableIndex = hash & mask;
    int next = CompactHashing.tableGet(requireTable(), tableIndex);
    if (next == UNSET) { // uninitialized bucket
      if (newSize > mask) {
        // Resize and add new entry
        mask = resizeTable(mask, CompactHashing.newCapacity(mask), hash, newEntryIndex);
      } else {

        this.dis = new DataInputStream(in);
        this.size = in.available();
    }


    public void align ( int mask ) throws IOException {
        int position = this.size - this.dis.available();
        int shift = position & mask - 1;
        if ( mask != 0 && shift != 0 )
            this.dis.skip(mask - shift);
    }


    public int available () throws IOException {
        return this.dis.available();
    }

	ch3 := make(chan Maskable, 1)
	doneCh := make(chan struct{})
	defer close(doneCh)
	// Mask matches maskString, should get result
	if err := ps.Subscribe(Mask(1), ch1, doneCh, func(entry Maskable) bool { return true }); err != nil {
		t.Fatalf("unexpected error: %v", err)
	}
	// Mask matches maskString, should get result
	if err := ps.Subscribe(Mask(1|2), ch2, doneCh, func(entry Maskable) bool { return true }); err != nil {