hello module for "Erlang erl_syntax - usage example" blog post.

hello.erl

-module(hello).
-export([send_hello/1, receive_hello/0]).

send_hello(To) ->
 To ! {hello, self()}.

receive_hello() ->
 receive
  {hello, From} ->
   {ok, From};
  Msg ->
   {unknown_msg, Msg}
 end. 

hello.erl.abstract.forms

[{attribute,1,file,{"../src/hello.erl",1}},
 {attribute,1,module,hello},
 {attribute,2,export,[{send_hello,1},{receive_hello,0}]},
 {function,4,send_hello,1,
     [{clause,4,
          [{var,4,'To'}],
          [],
          [{op,5,'!',
               {var,5,'To'},
               {tuple,5,[{atom,5,hello},{call,5,{atom,5,self},[]}]}}]}]},
 {function,7,receive_hello,0,
     [{clause,7,[],[],
          [{'receive',8,
               [{clause,9,
                    [{tuple,9,[{atom,9,hello},{var,9,'From'}]}],
                    [],
                    [{tuple,10,[{atom,10,ok},{var,10,'From'}]}]},
                {clause,11,
                    [{var,11,'Msg'}],
                    [],
                    [{tuple,12,[{atom,12,unknown_msg},{var,12,'Msg'}]}]}]}]}]},
 {eof,13}]