Elixir

Custom types

Apr 6, 2016

Use @type to define custom types. For example, we can imagine definining types in an API client:

@type body           :: any
@type status_code    :: integer
@type request_method :: :get | :put | :post | :delete | :put | :patch | :head
@type header         :: { binary, binary }
@type response       :: { status_code, any, [header] }
@type payload        :: %Payload{ method: request_method, id: binary, size: integer }

You can use custom types in the definition of types, such as how the above header type is used in response.

Additional reading: