> Elixir is a pure functional language
No, it is not.
No, it is not.
Your comment just points what is wrong, without any help to guide those who would like to know more, be them the author or a reader. It is interesting because you just dismissed everything the article was about: being empathetic and providing guidance.
For the curious, I understand a pure functional language one that explicitly marks all side-effects, for example, by using monads. So Elixir indeed does not seem to be a pure language. More information can be found on wikipedia: http://en.wikipedia.org/wiki/Purely_functional
This is exactly what I did. The author made an error, which I corrected without any other commentary or name-calling, and which the author then corrected. This is the only guideline which is relevant to what I wrote.