Table doesn't exist exception when using arrayExists

[OmarBazaraa]

I have the following table:

CREATE TABLE test.table
(
    Id      UInt64,
    Arr1    Array(String),
    Arr2    Array(String)
)
ENGINE = MergeTree()
ORDER BY (Id);

Whenever I run this simple query, I get that strange error that I'm not expecting ...

SELECT arrayExists(x -> (x NOT IN (Arr2)), Arr1)
FROM test.table

Query id: 1407dc4e-1176-4bd3-9d93-e2706eeef12b

Received exception from server (version 21.1.2):
Code: 60. DB::Exception: Received from localhost:9440. DB::Exception: Table default.Arr2 doesn't exist: While processing arrayExists(x -> (x NOT IN (Arr2)), Arr1).

Why is ClickHouse considering Arr2 as a table?!

[alexey-milovidov]

It recognizes the syntax x IN table and parentheses around table do nothing.
In this query the syntax is ambiguous. This should be improved.