parse
foo
----
error: invalid column rewrites expression (expected -> operator)

parse
1 + 2
----
error: invalid column rewrites expression (expected -> operator)

parse
a -> b
----
error: missing parens around "before" expression

parse
(a) -> b
----
error: missing parens around "after" expression

parse
(a) -> (b), (c) -> (d)
----
(a) -> (b)
(c) -> (d)

parse
(a) -> (b), (c) -> (d)
----
(a) -> (b)
(c) -> (d)

parse
(a+1) -> (b+2), (c+10) -> (d+20)
----
(a + 1) -> (b + 2)
(c + 10) -> (d + 20)

parse
(ts::STRING) -> ((ts AT TIME ZONE 'utc')::STRING)
----
(ts::STRING) -> ((timezone('utc', ts))::STRING)

parse
(mod(fnv32(ts::STRING),4)) -> (mod(fnv32((ts AT TIME ZONE 'utc')::STRING), 4))
----
(mod(fnv32(ts::STRING), 4)) -> (mod(fnv32((timezone('utc', ts))::STRING), 4))
