An attempt to actually answer the question, using knowledge from the link. Elixir does not do matching with the = operator , it does something called rebinding. The code example shows how Elixir can be made to behave like Erlang, which is completely illogical to me as a total new user of the language. I hope to revisit this answer in the future to write something better :).
So Elixir uses pattern matchin when the variable is preceded with a ^ instead of rebinding. My question is : in a big piece of code how those one keep track of first use and use this notation?It would be great if anyone can provide a good answer to that :).