}
	// T is not the empty interface (i.e., the type set of T is restricted)

	// An interface V with an empty type set satisfies any interface.
	// (The empty set is a subset of any set.)
	Vi, _ := Vu.(*Interface)
	if Vi != nil && Vi.typeSet().IsEmpty() {
		return true
	}
	// type set of V is not empty

	// No type with non-empty type set satisfies the empty type set.
	if Ti.typeSet().IsEmpty() {
		if cause != nil {

	tset *_TypeSet // type set described by this interface, computed lazily
}

// typeSet returns the type set for interface t.
func (t *Interface) typeSet() *_TypeSet { return computeInterfaceTypeSet(t.check, nopos, t) }

// emptyInterface represents the empty interface
var emptyInterface = Interface{complete: true, tset: &topTypeSet}

For inbound requests, the new [Request.Pattern] field contains the [ServeMux]
pattern (if any) that matched the request. This field is not set when

	_, ok := Unalias(t).(*TypeParam)
	return ok
}

// hasEmptyTypeset reports whether t is a type parameter with an empty type set.
// The function does not force the computation of the type set and so is safe to
// use anywhere, but it may report a false negative if the type set has not been
// computed yet.
func hasEmptyTypeset(t Type) bool {
	if tpar, _ := Unalias(t).(*TypeParam); tpar != nil && tpar.bound != nil {

	D        MultiFlag
	I        MultiFlag
	PrintOut int
	DebugV   bool
)

func init() {
	flag.Var(&D, "D", "predefined symbol with optional simple value -D=identifier=value; can be set multiple times")
	flag.Var(&I, "I", "include directory; can be set multiple times")
	flag.BoolVar(&DebugV, "v", false, "print debug output")
	flag.Var(objabi.NewDebugFlag(&DebugFlags, nil), "d", "enable debugging settings; try -d help")

The new [ParseCookie] function parses a Cookie header value and
returns all the cookies which were set in it. Since the same cookie
name can appear multiple times the returned Values can contain
more than one value for a given key.

The new [ParseSetCookie] function parses a Set-Cookie header value and

On Windows, the mode bits reported by [Lstat] and [Stat] for
reparse points changed. Mount points no longer have [ModeSymlink] set,
and reparse points that are not symlinks, Unix sockets, or dedup files
now always have [ModeIrregular] set.
This behavior is controlled by the `winsymlink` setting.
For Go 1.23, it defaults to `winsymlink=1`.

Maintaining vendor directories
==============================

Before updating vendor directories, ensure that module mode is enabled.
Make sure that GO111MODULE is not set in the environment, or that it is
set to 'on' or 'auto', and if you use a go.work file, set GOWORK=off.

Requirements may be added, updated, and removed with 'go get'.
The vendor directory may be updated with 'go mod vendor'.
A typical sequence might be:

	// If enableCoreTypeUnification is set, unification will consider
	// the core types, if any, of non-local (unbound) type parameters.
	enableCoreTypeUnification = true

	// If traceInference is set, unification will print a trace of its operation.
	// Interpretation of trace:
	//   x ≡ y    attempt to unify types x and y
	//   p ➞ y    type parameter p is set to type y (p is inferred to be y)

	return res
}

func (a *Alias) cleanup() {
	// Ensure a.actual is set before types are published,
	// so Unalias is a pure "getter", not a "setter".
	actual := Unalias(a)

	if actual == Typ[Invalid] {
		// We don't set a.actual to Typ[Invalid] during type checking,
		// as it may indicate that the RHS is not fully set up.
		a.actual = actual
	}