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NamedArgs

Inspired by Named Arguments with Elixir

Allows you to use named arguments similar to Ruby's named arguments. For example, in Ruby

def introduction(name: 'Sarah', birthday: "1985-12-30")  
  puts "Hi my name is #{name} and I was born on #{birthday}"
end

However in Elixir, using a default argument ends up dropping the other values.

defmodule Talk do  
  def introduction(opts \\ [name: "Sarah", birthday: "1985-12-30"]) do
    IO.puts "Hi my name is #{opts[:name]} and I was born on #{opts[:birthday]}"
  end
end
# Drops the birthday
Talk.introduction(name: "Joe") # => Hi my name is Joe and I was born on
# Drops the name
Talk.introduction(birthday: "1985-12-30") # => Hi my name is  and I was born on 1985-12-30

With NamedArgs you can instead do the following:

defmodule Talk do
  use NamedArgs
  def introduction(opts \\ [name: "Sarah", birthday: "1985-12-30"]) do
    IO.puts "Hi my name is #{opts[:name]} and I was born on #{opts[:birthday]}"
  end
end
# No params!
Talk.introduction # => Hi my name is Sarah and my birthday is 1985-12-30
# Keeps the birthday
Talk.introduction(name: "Joe") # => Hi my name is Joe and I was born on 1985-12-30
# Keeps the name
Talk.introduction(birthday: "1986-01-01") # => Hi my name is Sarah and I was born on 1986-01-01
# Order does not matter!
Talk.introduction(birthday: "1986-01-01", name: "Joe") # => Hi my name is Joe and I was born on 1986-01-01

Installation

This package is available in Hex, to install:

  1. Add named_args to your list of dependencies in mix.exs:
  def deps do
    [
      {:named_args, "~> 0.1.0"}
    ]
  end

But it doesn't create a variable with the same name?

Yup, I'm still not sure if thats a desired feature or not. Because it would implicitly create a variable that you may or may not decide to use, it goes against a lot of the philosophies that Elixir follows in regard to explicit coding. And the compiler would warn you about it (and it couldn't be fixed either).

If possible to remove the compiler warning this feature may become more attractive. Please let me know if you have ideas about this!