}
		return fmt.Sprintf("types.NewChan(%s, %s)", i.subtype(t.Value), dir)
	case *ast.FuncType:
		return fmt.Sprintf("newSig(%s, %s)", i.fields(t.Params, false), i.fields(t.Results, false))
	case *ast.InterfaceType:
		if len(t.Methods.List) != 0 {
			log.Fatal("non-empty interfaces unsupported")
		}
		return "types.Types[types.TINTER]"
	case *ast.MapType:

		p.fieldDecl(typ)
		return false
	})

	return typ
}

// InterfaceType = "interface" "{" { ( MethodDecl | EmbeddedElem ) ";" } "}" .
func (p *parser) interfaceType() *InterfaceType {
	if trace {
		defer p.trace("interfaceType")()
	}

	typ := new(InterfaceType)
	typ.pos = p.pos()

	p.want(_Interface)
	p.want(_Lbrace)

			tok(n.Lbrack, len("[")),
			tok(n.Rbrack, len("]")))

	case *ast.IndexListExpr:
		children = append(children,
			tok(n.Lbrack, len("[")),
			tok(n.Rbrack, len("]")))

	case *ast.InterfaceType:
		children = append(children,
			tok(n.Interface, len("interface")))

	case *ast.KeyValueExpr:
		children = append(children,
			tok(n.Colon, len(":")))

	case *ast.LabeledStmt:

		return f64hash(p, h)
	case abi.Complex64:
		return c64hash(p, h)
	case abi.Complex128:
		return c128hash(p, h)
	case abi.String:
		return strhash(p, h)
	case abi.Interface:
		i := (*interfacetype)(unsafe.Pointer(t))
		if len(i.Methods) == 0 {
			return nilinterhash(p, h)
		}
		return interhash(p, h)
	case abi.Array:
		a := (*arraytype)(unsafe.Pointer(t))
		for i := uintptr(0); i < a.Len; i++ {

		for _, t := range n.TagList {
			if t != nil {
				w.node(t)
			}
		}

	case *Field:
		if n.Name != nil {
			w.node(n.Name)
		}
		w.node(n.Type)

	case *InterfaceType:
		w.fieldList(n.MethodList)

	case *FuncType:
		w.fieldList(n.ParamList)
		w.fieldList(n.ResultList)

	case *MapType:
		w.node(n.Key)
		w.node(n.Value)

	case *ChanType:

	case *FuncType:
		if n.TypeParams != nil {
			Walk(v, n.TypeParams)
		}
		if n.Params != nil {
			Walk(v, n.Params)
		}
		if n.Results != nil {
			Walk(v, n.Results)
		}

	case *InterfaceType:
		Walk(v, n.Methods)

	case *MapType:
		Walk(v, n.Key)
		Walk(v, n.Value)

	case *ChanType:
		Walk(v, n.Value)

	// Statements
	case *BadStmt:
		// nothing to do

		check.use(e0)

	case *syntax.FuncType:
		typ := new(Signature)
		setDefType(def, typ)
		check.funcType(typ, nil, nil, e)
		return typ

	case *syntax.InterfaceType:
		typ := check.newInterface()
		setDefType(def, typ)
		check.interfaceType(typ, e, def)
		return typ

	case *syntax.MapType:
		typ := new(Map)
		setDefType(def, typ)

		typ.key = check.varType(e.Key)

		return r.signature(nil, nil, nil)
	case pkgbits.TypeSlice:
		return types.NewSlice(r.typ())
	case pkgbits.TypeStruct:
		return r.structType()
	case pkgbits.TypeInterface:
		return r.interfaceType()
	case pkgbits.TypeUnion:
		return r.unionType()
	}
}

func (r *reader) structType() *types.Struct {
	fields := make([]*types.Var, r.Len())
	var tags []string
	for i := range fields {

		return typ

	case *ast.FuncType:
		typ := new(Signature)
		setDefType(def, typ)
		check.funcType(typ, nil, e)
		return typ

	case *ast.InterfaceType:
		typ := check.newInterface()
		setDefType(def, typ)
		check.interfaceType(typ, e, def)
		return typ

	case *ast.MapType:
		typ := new(Map)
		setDefType(def, typ)

		typ.key = check.varType(e.Key)

}

const predeclReserved = 32

type itag uint64

const (
	// Types
	definedType itag = iota
	pointerType
	sliceType
	arrayType
	chanType
	mapType
	signatureType
	structType
	interfaceType
	typeParamType
	instanceType
	unionType
)

// iImportData imports a package from the serialized package data
// and returns the number of bytes consumed and a reference to the package.