case *ArrayType, *StructType, *FuncType, *InterfaceType, *SliceType, *MapType, *ChanType:
		return true
	case *Operation:
		return isTypeElem(x.X) || (x.Y != nil && isTypeElem(x.Y)) || x.Op == Tilde
	case *ParenExpr:
		return isTypeElem(x.X)
	}
	return false
}

// VarSpec = IdentifierList ( Type [ "=" ExpressionList ] | "=" ExpressionList ) .
func (p *parser) varDecl(group *Group) Decl {
	if trace {

			b = true
		}
	}
	return b
}

func filterType(typ Expr, f Filter, export bool) bool {
	switch t := typ.(type) {
	case *Ident:
		return f(t.Name)
	case *ParenExpr:
		return filterType(t.X, f, export)
	case *ArrayType:
		return filterType(t.Elt, f, export)
	case *StructType:
		if filterFieldList(t.Fields, f, export) {
			t.Incomplete = true
		}

		}

	case *syntax.IndexExpr:
		check.verifyVersionf(e, go1_18, "type instantiation")
		return check.instantiatedType(e.X, syntax.UnpackListExpr(e.Index), def)

	case *syntax.ParenExpr:
		// Generic types must be instantiated before they can be used in any form.
		// Consequently, generic types cannot be parenthesized.
		return check.definedType(e.X, def)

	case *syntax.ArrayType:

	case *ast.IndexExpr, *ast.IndexListExpr:
		ix := typeparams.UnpackIndexExpr(e)
		check.verifyVersionf(inNode(e, ix.Lbrack), go1_18, "type instantiation")
		return check.instantiatedType(ix, def)

	case *ast.ParenExpr:
		// Generic types must be instantiated before they can be used in any form.
		// Consequently, generic types cannot be parenthesized.
		return check.definedType(e.X, def)

	case *ast.ArrayType:

			early.Append(init...)

			switch ll := l.(type) {
			case *ir.IndexExpr:
				if ll.X.Type().IsArray() {
					save(&ll.Index)
					l = ll.X
					continue
				}
			case *ir.ParenExpr:
				l = ll.X
				continue
			case *ir.SelectorExpr:
				if ll.Op() == ir.ODOT {
					l = ll.X
					continue
				}
			}
			break
		}

		var name *ir.Name
		switch l.Op() {

	const want = `package p

func f()
`

	if got != want {
		t.Fatalf("got:\n%s\nwant:\n%s\n", got, want)
	}
}

// TestChanType tests that the tree for <-(<-chan int), without
// ParenExpr, is correctly formatted with parens.
// Test case for issue #63362.
func TestChanType(t *testing.T) {
	expr := &ast.UnaryExpr{
		Op: token.ARROW,
		X: &ast.CallExpr{
			Fun: &ast.ChanType{
				Dir:   ast.RECV,

	case *ast.Ident, *ast.BasicLit, *ast.SelectorExpr:
		// An identifier denoting a constant, a constant literal,
		// or a qualified identifier (imported untyped constant).
		// No operands to take care of.

	case *ast.ParenExpr:
		check.updateExprType0(x, x.X, typ, final)

	case *ast.UnaryExpr:
		// If x is a constant, the operands were constants.
		// The operands don't need to be updated since they

		return baseTypeName(t.X)
	case *ast.SelectorExpr:
		if _, ok := t.X.(*ast.Ident); ok {
			// only possible for qualified type names;
			// assume type is imported
			return t.Sel.Name, true
		}
	case *ast.ParenExpr:
		return baseTypeName(t.X)
	case *ast.StarExpr:
		return baseTypeName(t.X)
	}
	return "", false
}

// An embeddedSet describes a set of embedded types.
type embeddedSet map[*namedType]bool

	// work for other invalid receivers, but we don't care. The
	// validity of receiver expressions is checked elsewhere.
	for {
		switch t := rtyp.(type) {
		case *syntax.ParenExpr:
			rtyp = t.X
		// case *ast.StarExpr:
		//      ptr = true
		// 	rtyp = t.X
		case *syntax.Operation:
			if t.Op != syntax.Mul || t.Y != nil {
				break
			}
			ptr = true
			rtyp = t.X

	// work for other invalid receivers, but we don't care. The
	// validity of receiver expressions is checked elsewhere.
	for {
		switch t := rtyp.(type) {
		case *ast.ParenExpr:
			rtyp = t.X
		case *ast.StarExpr:
			ptr = true
			rtyp = t.X
		default:
			break L
		}
	}

	// unpack type parameters, if any
	switch rtyp.(type) {