Erlang Records Module

records.erl

-module(records).
-compile(export_all).
-include("records.hrl").

-record(robot, {name,
                type=industrial,
                hobbies,
                details=[]}).
-record(user, {id, name, group, age}).

first_robot() ->
    #robot{name="Mechatron",
           type=handmade, 
           details=["Moved by a small man inside"]}.

car_factory(CorpName) ->
    #robot{name=CorpName, hobbies="building cars"}.

%% use pattern matching to filter
admin_panel(#user{name=Name, group=admin}) ->
    Name ++ " is allowed!";
admin_panel(#user{name=Name}) ->
    Name ++ " is not allowed".

%% can extend user without problem
adult_section(U = #user{}) when U#user.age >= 18 ->
    %% Show stuff that can't be written in such a text
    allowed;
adult_section(_) ->
    %% redirect to sesame street site
    forbidden.

repairman(Rob) ->
    Details = Rob#robot.details,
    NewRob = Rob#robot{details=["Repaired by repairman"|Details]},
    {repaired, NewRob}.


included() -> #included{some_field="Some value"}.

records.hrl

%% this is a .hrl (header) file.
-record(included, {some_field,
                   some_default = "yeah!",
                   unimaginative_name}).