In postgres it allows doing:
SELECT (ARRAY[1,2])[1] AS a
But it does not allow:
SELECT ARRAY[1,2][1] AS a
This seems a bit arbitrary to me that it would be ambiguous when not including parens around the array literal, what would be an example where this would be ambiguous? Most languages have a construct of a direct array access, so curious why it's considered ambiguous in PG.