This is a rework of the example for AutoInject. The example does not run on its own. This one does if you bundle dry-container and dry-auto_inject

example-dry-auto_inject.rb

require 'dry-container'
require 'dry-auto_inject'

# set up your container
my_container = Dry::Container.new

my_container.register(:data_store, -> { {users:[]} })
my_container.register(:user_repository, -> { my_container[:data_store][:users] })
my_container.register(:persist_user, -> { PersistUser.new })

# set up your auto-injection function
AutoInject = Dry::AutoInject(my_container)

# then simply include it in your class providing which dependencies should be
# injected automatically from the configured container
class PersistUser
  include AutoInject[:user_repository]

  def call(user)
    user_repository << user
  end
end

persist_user = my_container[:persist_user]

persist_user.call(name: 'Jane')