elvanja / behaviour-introspection

Removes the need for factories. Enables open for extension, closed for modification.

Behaviour Introspection

Allows you to gather all modules that implement a specified behaviour so that operations can be performed on them without tight coupling.

This removes the need for specific module registration.

Behaviours are the equivalent to interfaces in Elixir.

Installation

The package can be installed as:

1. Add behaviour_introspection to your list of dependencies in mix.exs:

```elixir
def deps do
  [{:behaviour_introspection, git: "[e-mail]:findmypast/behaviour-introspection.git",tag:"0.1.0"}]
end
```

2. Ensure behaviour_introspection is started before your application:

```elixir
def application do
  [applications: [:behaviour_introspection]]
end
```

3. Run 'mix deps.get'

Example

# An example behaviour with a description function.
defmodule Test.SimpleBehaviour do
  @callback description() :: String.t
end

# A couple of implementations of a behaviour.
defmodule Test.SimpleImplementation1 do
  @behaviour Test.SimpleBehaviour

  def description do
    "This is the first simple implementation"
  end
end

# Call all description methods on any modules that implement SimpleBehaviour.

BehaviourIntrospection.available_modules_with_behaviour(Test.SimpleBehaviour)
  |> Enum.each(fn (x) -> IO.inspect(x.description) end)

# Outputs

"This is the first simple implementation"

To add a new implementation simply create the new module in your project with the SimpleBehaviour, as follows:

defmodule Test.SimpleImplementation2 do
  @behaviour Test.SimpleBehaviour

  def description do
    "This is the second simple implementation"
  end
end

# Outputs

"This is the first simple implementation"
"This is the second simple implementation"