closest thing to arrays in Elixir

Question

what is the closest thing to Arrays in Elixir. By arrays I mean, a container for values which I can access in constant time.

I've looked at tuple, but according to the documentation:

Tuples are not meant to be used as a “collection” type (which is also suggested by the absence of an implementation of the Enumerable protocol for tuples): they’re mostly meant to be used as a fixed-size container for multiple elements.

What I actually want to do: I want to store n processes in an array and periodically pick a random process and send it a message. I'm open to other suggestions too.

Answer 1

I ended up using a combination of list and registry since I was working with processes. I got many responses on Elixir forum which I'm listing below for future reference:

1. Tuple: stored continuous in memory, constant access time, editing results in copying whole structure. Does not implement Enumerable protocol.
2. linked-List: O(n) access time, prefixing is cheaper than suffixing. Implements Enumerable protocol.
3. Map: O(log n) read, write, delete time. Also implements Enumerable protocol.
4. :array: array module from Erlang.
5. registry: (applicable only if storing processes) A local, decentralized and scalable key-value process storage.

Also, note 2 and 3 (List and Map) are persistent data structures.

Answer 2

There are also two Elixir packages Arrays and Tensor that provide similar functionalities.

Answer 3

Elixir has an array module via erlang: http://erlang.org/doc/man/array.html