can do: runtime rewrites of the plan, so yu can do stuff like:

SELECT '   WoRlD  '
    |> trim('|>')
    |> lower('|>')
    |> regexp_replace('|>', 'w', 'g')
    |> concat('!! ', '|>', ' !!') AS hello;
    -- !! gorld !!

... but only with text, since the placeholder, for now, is text only.

can't do (yet):

• non text piping
• nested horrible nonsense, i.e., you can do:

select concat('!!', 'HELLO' |> lower('|>'), '!!') AS hello;

but not:

select 'world' |> concat('|>', 'HELLO' |> lower('|>'), '!!') AS hello;