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@kaspth
Created June 10, 2023 14:42
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Making Ruby better at object proxying, so we don't need to add `user_name` etc. for Law of Demeter.
class Object::Proxy < SimpleDelegator
def initialize(object, **values)
super(object)
@values = values
end
def method_missing(name, ...)
@values.fetch(name) { super }
end
end
module Object::Proxied
def self.included(klass)
klass.define_singleton_method(:proxied) { |object = new, **values| Object::Proxy.new(object, **values) }
end
def proxied(**values)
self.class.proxied(self, **values)
end
end
class User < Data.define(:name, :email_address)
include Object::Proxied
end
class Post
# belongs_to :user
def user = super || build_user.proxied(name: "Unknown")
end
Post.new.user.name # => "Unknown"
Post.new.user.save! # => true # The User model doesn't have to know about and then guard against "Unknown" being saved to the database.
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