I have Ruby class into which I want to include both class and instance methods. Following the pattern described here, I'm currently using the following:
class SomeObject
include SomeObject::Ability
def self.some_builder_method(params)
# use some_class_method ...
end
end
module SomeObject::Ability
module ClassMethods
def some_class_method(param)
# ...
end
end
def self.included(klass)
klass.extend(ClassMethods)
end
def some_instance_method
# ...
end
end
I'd rather not make two separate modules (one being included and the other being extended), because all the methods in my module logically fit together. On the other hand, this pattern a) requires me to define an additional ClassMethods
module and b) requires me to write a boilerplate self.included
method for every module.
Is there a better way to do this?
Edit 1: I've found another way, but I'm unsure if this is better than the first.
module Concern
def included(base)
# Define instance methods.
instance_methods.each do |m|
defn = instance_method(m)
base.class_eval { define_method(m, defn) }
end
# Define class methods.
(self.methods - Module.methods).each do |m|
unless m == __method__
base.define_singleton_method(m, &method(m))
end
end
end
end
module SomeModule
extend Concern
def self.class_m
puts "Class"
end
def instance_m
puts "Instance"
end
end
class Allo
include SomeModule
end
Allo.class_m # => "Class"
Allo.new.instance_m # => "Instance"
If I understand you correctly, you really just want to use ActiveSupport::Concern
:
module PetWorthy
extend ActiveSupport::Concern
included do
validates :was_pet, inclusion: [true, 'yes']
end
def pet #instance method
end
module ClassMethods
def find_petworthy_animal
# ...
end
end
end
class Kitty
include PetWorthy
end
Kitty.find_petworthy_animal.pet
You (hopefully obviously) don't need to use the included
method if you don't have any behavior to trigger on include, but I put it in just to demonstrate.