saturnflyer/behavioral

Add and remove behaviors to individual Ruby objects

Behavioral

Add behavior to individual objects and remove it later while preserving the existing behavior.

This is similar to Casting in that it adds and removes behaviors and preserves self but it's different in that you can still use super inside your methods.

Usage

Add Behavioral to your classes to add new features or override existing ones. Later you may remove your behaviors:

class Person
  def initialize(name)
    @name = name
  end
  attr_reader :name
  
  include Behavioral
end

module Greeter
  def hello
    "Hello, I am #{self.name}"
  end
  
  def name
    "The Greeter #{super}"
  end
end

person = Person.new('Jim').with_behaviors(Greeter)
person.hello #=> "Hello, I am Jim"

person.without_behaviors(Greeter)
person.hello #=> NoMethodError

This does not alter the ancestry

When you add behaviors, the methods are copied to the singleton_class of your object. Later, if you ask the object if it is of that type, the answer will be false.

person = Person.new('Jim').with_behaviors(Greeter)
person.is_a?(Greeter) #=> false

#alternative
person = Person.new('Jim').extend(Greeter)
person.is_a?(Greeter) #=> true

Installation

Add this line to your application's Gemfile:

gem 'behavioral'

And then execute:

$ bundle

Or install it yourself as:

$ gem install behavioral

Contributing

1. Fork it
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create new Pull Request