```
$ ~/arc/build/clickhouse/programs/clickhouse client
ClickHouse client version 21.2.1.1-arcadia.
Connecting to localhost:9000 as user default.
Connected to ClickHouse server version 21.2.1 revision 54447.

max42-dev.sas.yp-c.yandex.net :) create table t(a Tuple(UInt8, UInt8)) engine = Log()

CREATE TABLE t
(
    `a` Tuple(UInt8, UInt8)
)
ENGINE = Log

Query id: b49dbb5d-d2a9-4c99-b90e-00c60edf2103

Ok.

0 rows in set. Elapsed: 0.005 sec. 

max42-dev.sas.yp-c.yandex.net :) insert into t values ((NULL, 42))

INSERT INTO t VALUES

Query id: 318d6f3e-f3bc-467c-85ff-62da908230dd

Logical error: 'Unexpected literal type inside Array: Nothing. It's a bug'.
Aborted (core dumped)
```

This is CH similar to one from Arcadia r7788360 (~fresh master version from GH).

(you don't have to strictly follow this form)

{
    const size_t size = elems.size();
    assertChar('(', istr);
    addElementSafe(elems, column, [&]
    {
        for (const auto i : ext::range(0, size))
        {
            skipWhitespaceIfAny(istr);
            if (i != 0)
            {
                assertChar(',', istr);
                skipWhitespaceIfAny(istr);
            }
            elems[i]->deserializeAsTextQuoted(extractElementColumn(column, i), istr, settings);
        }
    });
    
    if (1 == elems.size())
    {
        skipWhitespaceIfAny(istr);
        
        checkChar(',', istr);
    }
    skipWhitespaceIfAny(istr);
    assertChar(')', istr);
}
void DataTypeTuple::serializeTextJSON(const IColumn & column, size_t row_num, WriteBuffer & ostr, const FormatSettings & settings) const