Programming Elixir

Behaviours

An Elixir behaviour is nothing more than a list of functions. A module that declares that it implements a particular behaviour must implement all of the associated functions. If it doesn’t, Elixir will generate a compilation warning.

A behaviour is therefore a little like an interface in Java. A module uses it to declare that it implements a particular interface. For example, an OTP GenServer should implement a standard set of callbacks (handle_call, handle_cast, and so on). By declaring that our module implements that behaviour, we let the compiler validate that we have actually supplied the necessary interface. This reduces the chance of an unexpected runtime error.

Defining Behaviours

We define a behaviour using the Elixir Behaviour ...