elixir - Keyword-based query returns undefined function for binding -

i trying use keyeword-based queries in order use lateral joins

i copy-pasting docs

automessage |> join(:inner, [am], in assoc(am, :app)) 

but complain with

undefined function a/0 

any ideas doing wrong?

ps. running on ecto. 2.0.5

most ecto.query.join/3 macro not imported scope, , query interpreted regular elixir code compiler.

ps. keyword-style query 1 using from/2 macro, using other macros pipe-style or direct-style (not sure terminology used here).