public:
  // Returns number of dimensions.
  virtual absl::Status NumDims(int* num_dims) const = 0;
  // Returns number of elements across all dimensions.
  virtual absl::Status NumElements(int64_t* num_elements) const = 0;
  // Returns size of specified dimension
  //
  // -1 indicates an unknown axis length; this is unreachable for most standard
  // ImmediateExecutionTensorHandles, but comes up for example when computing

  float A_vals[] = {1.0f, 2.0f, 3.0f, 4.0f};
  int64_t A_dims[] = {2, 2};
  AbstractTensorHandlePtr A;
  {
    AbstractTensorHandle* A_raw;
    absl::Status s = TestTensorHandleWithDims<float, TF_FLOAT>(
        ctx_.get(), A_vals, A_dims, 2, &A_raw);
    ASSERT_EQ(errors::OK, s.code()) << s.message();
    A.reset(A_raw);
  }
  float B_vals[] = {.5f, -1.0f, 1.0f, 1.0f};
  int64_t B_dims[] = {2, 2};
  AbstractTensorHandlePtr B;

pkg sync, method (*Map) Clear() #61696
pkg sync/atomic, func AndInt32(*int32, int32) int32 #61395
pkg sync/atomic, func AndInt64(*int64, int64) int64 #61395
pkg sync/atomic, func AndUint32(*uint32, uint32) uint32 #61395
pkg sync/atomic, func AndUint64(*uint64, uint64) uint64 #61395
pkg sync/atomic, func AndUintptr(*uintptr, uintptr) uintptr #61395
pkg sync/atomic, func OrInt32(*int32, int32) int32 #61395
pkg sync/atomic, func OrInt64(*int64, int64) int64 #61395

                                 const int64_t* dims, int num_dims) {
  DCHECK(index >= 0 && index < shape_list->num_items);
  TF_ShapeAndType& shape = shape_list->items[index];
  DCHECK(shape.dims == nullptr) << "Shape at " << index << " is already set!";
  DCHECK(num_dims >= 0) << "Number of dimensions cannot be negative!";
  shape.num_dims = num_dims;
  shape.dims = new int64_t[num_dims];

// gradient registerer to instantiate a GradientFunction.
struct ForwardOperation {
 public:
  string op_name;
  std::vector<AbstractTensorHandle*> inputs;
  std::vector<AbstractTensorHandle*> outputs;
  std::vector<int64_t> skip_input_indices;
  AttrBuilder attrs;
};

using GradientFunctionFactory =
    std::function<GradientFunction*(const ForwardOperation& op)>;

// Map from op name to a `GradientFunctionFactory`.

TF_CAPI_EXPORT extern void TFE_CollectiveOpsCheckPeerHealth(
    TFE_Context* ctx, const char* task, int64_t timeout_in_ms,
    TF_Status* status);

// Information about the shape of a Tensor and its type.
struct TF_ShapeAndType {
  // Number of dimensions. -1 indicates unknown rank.
  int num_dims;
  // Array of dimensions. -1 indicates unknown dim.
  int64_t* dims;
  // The data type. May be 0 to denote unknown type.
  TF_DataType dtype;
};

	if len(ps.subs) != 2 {
		t.Fatalf("expected 2 subscribers")
	}
	if want, got := int32(2), ps.NumSubscribers(Mask(1)); got != want {
		t.Fatalf("want %d subscribers, got %d", want, got)
	}
	if want, got := int32(2), ps.NumSubscribers(Mask(2)); got != want {
		t.Fatalf("want %d subscribers, got %d", want, got)
	}
	if want, got := int32(2), ps.NumSubscribers(Mask(1|2)); got != want {
		t.Fatalf("want %d subscribers, got %d", want, got)

	}

	for _, f := range fields {
		checkSchemaField(t, user, f, func(f *schema.Field) {})
	}
}

type (
	ID      int64
	INT     int
	INT8    int8
	INT16   int16
	INT32   int32
	INT64   int64
	UINT    uint
	UINT8   uint8
	UINT16  uint16
	UINT32  uint32
	UINT64  uint64
	FLOAT32 float32
	FLOAT64 float64
	BOOL    bool
	STRING  string
	TIME    time.Time

  // Returns the AbstractFunction as a FunctionDef.
  virtual void GetNameAttrList(
      tensorflow::NameAttrList* name_and_attrs) const = 0;

  virtual bool GetInt(absl::string_view, int64_t* result) const = 0;
  virtual bool GetFloat(absl::string_view attr_name, float* result) const = 0;
  virtual bool GetBool(absl::string_view attr_name, bool* result) const = 0;

	types  Mask
	filter func(entry T) bool
}

// PubSub holds publishers and subscribers
type PubSub[T Maskable, M Maskable] struct {
	// atomics, keep at top:
	types          uint64
	numSubscribers int32
	maxSubscribers int32

	// not atomics:
	subs []*Sub[T]
	sync.RWMutex
}

// Publish message to the subscribers.
// Note that publish is always non-blocking send so that we don't block on slow receivers.