Elixir for Ruby developers: the three most important differences

Many developers who come from a Ruby background are attracted to Elixir due to its similarities in syntax. However, the article highlights that these similarities are only surface-level, as Elixir and Ruby have significant differences in their underlying designs. This article aims to provide a brief introduction to Elixir for Ruby developers, focusing on the three most important differences between the two languages.

The first major difference is that Elixir is a functional language, not object-oriented like Ruby. Elixir does not have classes or instance methods. Instead, developers write functions that are grouped into modules. For example, in Ruby, a string like "this" is an instance of the String class, with various instance methods like upcase, reverse, or length. In Elixir, String is a module that contains functions that apply to strings. So instead of calling name.upcase in Ruby, developers would write String.upcase(name) in Elixir.

The second difference highlighted is that Elixir has modules like Integer, List, and Float, each containing functions specific to their respective types. These modules allow developers to perform operations on these types using functions. For example, Elixir provides different ways to test whether a regex matches a string, with the first argument typically having the same type as the module.

Overall, this article serves as a starting point for Ruby developers looking to learn Elixir. It emphasizes the need to understand the fundamental differences between the two languages, particularly in terms of their functional vs. object-oriented nature and the use of modules for organizing code.