There are a lot more books out for Elixir and it is considered more mature than Elm at this moment in time. But I guess it could depend on two things:

• Do you have any experience with either (or front end or back end?)
• Which excites you the most?

Personally I am learning Elixir first and Elm second

That’s going to make matters extremely difficult - there really is no escaping JavaScript when developing web applications.

You can improve matters with Functional-Light JavaScript and JavaScript Allongé, the “Six” Edition after you get the basics down first (see also ECMAScript book).

As such there is “no real hurry” with Elm - it’s probably good enough to get a hold of the Elm in Action MEAP and simply work through each chapter as it is made available and reinforce what you have learned by referencing that material on elm-lang.org.

Focus some time on Elixir before you get into Phoenix (which in my opinion is somewhat macro heavy which can be a bit disorienting for neophytes).

Is elixir good for beginner programmer?

I think you’ll be better off learning Elixir first if you don’t have a strong functional background. Elixir has more resources available and is an easier language to use, which should get you to writing more functional code. Elm is very strict about types and the way you structure logic, so it’s more disciplined, and it’s also still very young and evolving. Your time right now is better spent learning Elixir and practicing the fundamental concepts of functional programming, because you will need them to use Elm effectively later.