This is a example on pattern matching.
Given the Map/Hash input:
input = %{name: "Alice Foo", points: 100, email: "alicefoo@myemail.com"}
The goal is to determine the user rank, by its points:
0..50
-> Starter50..200
-> Member>200
-> Veteran
The code in Elixir using pattern matching:
defmodule Rank do
@moduledoc """
Offers means to perform user ranking computations.
"""
@typedoc """
A user rank.
"""
@type rank :: :starter | :member | :veteran
@doc """
Finds the rank of a given user.
"""
@spec find(%{points: integer()}) :: rank()
def find(%{points: n}) when n <= 50, do: :starter
def find(%{points: n}) when n <= 200, do: :member
def find(_user), do: :veteran
end
Here's how you use it:
iex(1)> Rank.find(input)
:member
The same code in Ruby:
class Rank
# Offer means to perform ranking computations.
# Finds the rank of a given user.
def self.find(user)
case user[:points]
when 0..50
:starter
when 50..200
:member
else
:veteran
end
end
end
And running it:
irb(main):001:0> Rank.find(input)
=> :member
Patter matching makes the code more elegant, expressive and easier to read.
I still like to read Ruby version more..
it’s just beautiful 🍷 like poems
but certainly, his team need Elixir for performance, which Ruby could be blamed for. Although, they could also just use Rust to avoid data race, gc event spike and memory errors/leak in runtime that any GC language could have.
otherwise, favoring new thing doesn’t mean old thing are bad. It may be just a more suitable, comfortable option to ppl that they got reasons to go for.