// multiExpr typechecks e and returns its value (or values) in list.
// If allowCommaOk is set and e is a map index, comma-ok, or comma-err
// expression, the result is a two-element list containing the value
// of e, and an untyped bool value or an error value, respectively.
// If an error occurred, list[0] is not valid.
func (check *Checker) multiExpr(e ast.Expr, allowCommaOk bool) (list []*operand, commaOk bool) {
	var x operand

// multiExpr typechecks e and returns its value (or values) in list.
// If allowCommaOk is set and e is a map index, comma-ok, or comma-err
// expression, the result is a two-element list containing the value
// of e, and an untyped bool value or an error value, respectively.
// If an error occurred, list[0] is not valid.
func (check *Checker) multiExpr(e syntax.Expr, allowCommaOk bool) (list []*operand, commaOk bool) {
	var x operand