A simple Nano ID implementation in Ruby

nano_id.rb

# frozen_string_literal: true

require 'securerandom'

module NanoID
  ALPHABET = [*'A'..'Z', *'a'..'z', *'0'..'9', '_', '-'].freeze

  module_function

  def nano_id(alphabet: ALPHABET, size: 21)
    SecureRandom.send(:choose, alphabet, size)
  end
end

include NanoID

puts nano_id