Understanding @behaviour

[peerreynders]

FYI:

Behaviours in Javascript?

I really like to use behaviors in Elixir but now I have to work with Javascript so I don’t have them. Is there a library that would let me have this functionality? Or maybe there is a native solution for this?

History of Behaviours?

I know there are some Erlang old timers here, who might know - what is the history behind the behaviour syntax / idea? From a semantic point of view I could say that we could just send callbacks into a specific ‘behaviour’ function to setup / do our work for us… Perhaps they were easier to pick or learn than sticking lambdas in function arguments / dependency injection…? Did the idea originally come from elsewhere? OO interfaces, are obvious, but they don’t seem super compelling when you are…

Why are behaviour methods referred to as "callbacks"?

Coming from an OO background, my first reaction is to think of behaviours as interfaces. So it makes sense that a module must define one or more functions outlined in a behaviour if it wishes to implement that behaviour. So why in Elixir are the behaviour’s functions referred to as “callbacks”? In other languages, a “callback” has quite different connotations which have little to do with inheritance. In fact, the page at https://elixir-lang.org/getting-started/typespecs-and-behaviours.html h…