// operator is "In", and the values array contains only "value". The requirements are ANDed.
  // +optional
  map<string, string> matchLabels = 1;

  // matchExpressions is a list of label selector requirements. The requirements are ANDed.
  // +optional
  // +listType=atomic
  repeated LabelSelectorRequirement matchExpressions = 2;
}

// A label selector requirement is a selector that contains values, a key, and an operator that

func validateCtx(ctx schedCtx, reqs event.SchedReqs) error {
	// Check thread requirements.
	if reqs.Thread == event.MustHave && ctx.M == NoThread {
		return fmt.Errorf("expected a thread but didn't have one")
	} else if reqs.Thread == event.MustNotHave && ctx.M != NoThread {
		return fmt.Errorf("expected no thread but had one")
	}

	// Check proc requirements.
	if reqs.Proc == event.MustHave && ctx.P == NoProc {

	CALL	runtime·libpreinit(SB)

	// Create a new thread to finish Go runtime initialization.
	MOVQ	_cgo_sys_thread_create(SB), AX
	TESTQ	AX, AX
	JZ	nocgo

	// We're calling back to C.
	// Align stack per ELF ABI requirements.
	MOVQ	SP, BX  // Callee-save in C ABI
	ANDQ	$~15, SP
	MOVQ	$_rt0_amd64_lib_go(SB), DI
	MOVQ	$0, SI
	CALL	AX
	MOVQ	BX, SP
	JMP	restore

nocgo:
	ADJSP	$16
	MOVQ	$0x800000, 0(SP)		// stacksize

	// operator is "In", and the values array contains only "value". The requirements are ANDed.
	// +optional
	MatchLabels map[string]string `json:"matchLabels,omitempty" protobuf:"bytes,1,rep,name=matchLabels"`
	// matchExpressions is a list of label selector requirements. The requirements are ANDed.
	// +optional
	// +listType=atomic

  // have two requirements that significantly complicate their design.
  // 1. Cancellation should propagate from the returned future to the input future(s).
  // 2. The returned futures shouldn't unnecessarily 'pin' their inputs after completion.
  //
  // A consequence of these requirements is that the delegate futures cannot be stored in
  // final fields.
  //

It explains:

  // have two requirements that significantly complicate their design.
  // 1. Cancellation should propagate from the returned future to the input future(s).
  // 2. The returned futures shouldn't unnecessarily 'pin' their inputs after completion.
  //
  // A consequence of these requirements is that the delegate futures cannot be stored in
  // final fields.
  //

 * interpolation can be added. This allows to have an entity which is useful in a runtime while preserving the model so
 * that it can be marshalled and unmarshalled without being tainted by runtime requirements.
 * </p>
 * <p>
 * With changes during 3.2.2 release MavenProject is closer to being immutable after construction with the removal of

These different <<sub:using_child_copy_specifications,levels of granularity>> in the copy specification allow you to handle most requirements that you will come across easily.

[[sec:copying_files]]
=== Understanding file copying

The basic process of copying files in Gradle is a simple one:

	x.Mul(x, a)
	y.Mul(y, b)
	x.Add(x, y)

	return x.Cmp(d) == 0
}

// euclidExtGCD is a reference implementation of Euclid's
// extended GCD algorithm for testing against optimized algorithms.
// Requirements: a, b > 0
func euclidExtGCD(a, b *Int) (g, x, y *Int) {
	A := new(Int).Set(a)
	B := new(Int).Set(b)

	// A = Ua*a + Va*b
	// B = Ub*a + Vb*b
	Ua := new(Int).SetInt64(1)
	Va := new(Int)