How to load an Erlang module within a Elixir/mix project?

Question

I have an Elixir project managed by mix. When started with iex -S mix all Elixir modules within my lib folder get loaded. An Erlang module in an .erl file within the lib folder doesn't.

I'd like to know either a) how do I load an Erlang module explicitly from my Elixir code or b) what do I have to do to have mix autoload the Erlang module, too. (Preferably both ;) )

Answer 1

Erlang modules that get compiled will get included automatically. If your local erlang module is in the lib/ folder though the problem may be that its not getting compiled.

The mix task that handles compiling erlang modules ( mix compile.erlang ) assumes the default path where the erlang modules are included is in a src/ directory.

If you'd prefer to place it somewhere else, you can adjust the configuration via the :erlc_paths parameter, in your project config in mix.exs . A bare bones example would look like:

def project do
  [
    app: :test,
    version: "0.1.0",
    elixir: "~> 1.6",
    erlc_paths: ["lib"],
    start_permanent: Mix.env() == :prod,
    deps: deps()
  ]
end