tuple_expr ::= '(' (expr',')* ')'
The last comma is optional.
However, in order to specify a 1-tuple, you have to use
That being said, 1-tuples will be removed in a future version of Impala.
(e_1, ..., e_n) has type
(E_1, ..., E_n) where
e_i is of type
All elements are evaluated from left to right and packed into a tuple value.
let x = (true, 23, 42.f);