// 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 {
		iface, _ := safeUnderlying(tpar.bound).(*Interface)
		return iface != nil && iface.tset != nil && iface.tset.IsEmpty()
	}
	return false
}

// isGeneric reports whether a type is a generic, uninstantiated type

// 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 {
		iface, _ := safeUnderlying(tpar.bound).(*Interface)
		return iface != nil && iface.tset != nil && iface.tset.IsEmpty()
	}
	return false
}

// isGeneric reports whether a type is a generic, uninstantiated type

	// be read outside the lock, but is only written to with lock held.
	//
	// Both wait & notify can wrap around, and such cases will be correctly
	// handled as long as their "unwrapped" difference is bounded by 2^31.
	// For this not to be the case, we'd need to have 2^31+ goroutines
	// blocked on the same condvar, which is currently not possible.
	notify uint32

	// List of parked waiters.
	lock mutex

	// However, it is only processing functions (which
	// are processed in a delayed fashion) that may
	// add more actions (such as nested functions), so
	// this is a sufficiently bounded process.
	for i := top; i < len(check.delayed); i++ {
		a := &check.delayed[i]
		if check.conf._Trace {
			if a.desc != nil {
				check.trace(a.desc.pos.Pos(), "-- "+a.desc.format, a.desc.args...)
			} else {

	for _, c := range p.Cmds {
		n.append(c.Copy().(*CommandNode))
	}
	return n
}

func (p *PipeNode) Copy() Node {
	return p.CopyPipe()
}

// ActionNode holds an action (something bounded by delimiters).
// Control actions have their own nodes; ActionNode represents simple
// ones such as field evaluations and parenthesized pipelines.
type ActionNode struct {
	NodeType
	Pos
	tr   *Tree

	// However, it is only processing functions (which
	// are processed in a delayed fashion) that may
	// add more actions (such as nested functions), so
	// this is a sufficiently bounded process.
	for i := top; i < len(check.delayed); i++ {
		a := &check.delayed[i]
		if check.conf.Trace {
			if a.desc != nil {
				check.trace(a.desc.pos.Pos(), "-- "+a.desc.format, a.desc.args...)
			} else {

 * the queue exceeds that value, the queue automatically removes its greatest element according to
 * its comparator (which might be the element that was just added). This is different from
 * conventional bounded queues, which either block or reject new elements when full.
 *
 * <p>This implementation is based on the <a
 * href="http://portal.acm.org/citation.cfm?id=6621">min-max heap</a> developed by Atkinson, et al.

	// because there will be a policy mapping stored on drives whose
	// filename is this parentUser: therefore, it needs to have only valid
	// filename characters and needs to have bounded length.
	{
		h := sha256.New()
		h.Write([]byte("openid:" + subFromToken + ":" + issFromToken))
		bs := h.Sum(nil)
		cred.ParentUser = base64.RawURLEncoding.EncodeToString(bs)
	}

 * the queue exceeds that value, the queue automatically removes its greatest element according to
 * its comparator (which might be the element that was just added). This is different from
 * conventional bounded queues, which either block or reject new elements when full.
 *
 * <p>This implementation is based on the <a
 * href="http://portal.acm.org/citation.cfm?id=6621">min-max heap</a> developed by Atkinson, et al.

				newCases = append(newCases, &ir.CaseClause{
					List: []ir.Node{ir.NewInt(base.Pos, int64(i))},
					Body: []ir.Node{c.jmp},
				})
			}
			// TODO: add len(newCases) case, mark switch as bounded
			sw2 := ir.NewSwitchStmt(base.Pos, caseVar, newCases)
			sw.Compiled.Append(typecheck.Stmt(sw2))
			interfaceCases = interfaceCases[:0]
		}

		if anyGoto != nil {