title: Reference to a field of a row object
body: <p>I'm having trouble accessing the fields of row objects which I have created in Presto. The Presto documentation <a href="https://prestodb.io/docs/current/language/types.html" rel="nofollow noreferrer">claims</a> "fields... are accessed with field reference operator." However that doesn't seem to work. This code reproduces the problem:</p>
  
  <pre><code>CREATE TABLE IF NOT EXISTS data AS
  SELECT * FROM (VALUES
      (1, 'Adam', 17),
      (2, 'Bill', 42)
  ) AS x (id, name, age);
  
  CREATE TABLE IF NOT EXISTS ungrouped_data AS
   WITH grouped_data AS (
    SELECT
      id,
      ROW(name, age) AS name_age
    FROM data
   )
  SELECT
    id,
    name_age.1 AS name,
    name_age.2 AS age
  FROM grouped_data;
  </code></pre>
  
  <p>Which returns an "extraneous input '.1'" error.</p>