parseChoices name s [(_, e)] =
    fail $ name ++ ": leftover characters when parsing '"
           ++ s ++ "': '" ++ e ++ "'"
parseChoices name s [(_, e)] =
    fail $ name ++ ": leftover characters when parsing '"
           ++ s ++ "': '" ++ e ++ "'"
parseChoices name s [(_, e)] =
    fail $ name ++ ": leftover characters when parsing '"
           ++ s ++ "': '" ++ e ++ "'"