Module: CallMeRuby

Defined in:
lib/call_me_ruby.rb

Overview

A mixin to implement publish/subscribe style callbacks in the class that includes this.

Defined Under Namespace

Modules: ClassMethods

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.included(cls) ⇒ Object

The self.included idiom. This is described in great detail in a fantastic blog post here:

www.railstips.org/blog/archives/2009/05/15/include-vs-extend-in-ruby/

Basically, this idiom allows us to add both instance and class methods to the class that is mixing this module into itself without forcing them to call extend and include for this mixin. You’ll see this idiom everywhere in the Ruby/Rails world, so we use it too.



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# File 'lib/call_me_ruby.rb', line 15

def self.included(cls)
  cls.extend(ClassMethods)
end

Instance Method Details

#callbacks ⇒ Object 



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# File 'lib/call_me_ruby.rb', line 31

def callbacks
  @callbacks ||= Hash.new { |h, k| h[k] = [] }
end

#publish(name, *args) ⇒ Object 



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# File 'lib/call_me_ruby.rb', line 40

def publish(name, *args)
  class_callback_methods = self.class.class_callbacks[name]
  callback_methods = callbacks[name]

  (class_callback_methods + callback_methods).each do |callback|
    result = (callback.respond_to?(:call) ? callback.call(*args) : send(callback, *args))
    # Exit early if the block explicitly returns `false`.
    return false if result == false
  end

  true
end

#subscribe(name, *methods, &block) ⇒ Object 



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# File 'lib/call_me_ruby.rb', line 35

def subscribe(name, *methods, &block)
  methods.each { |method| callbacks[name] << method }
  callbacks[name] << block if block_given?
end

#subscribed?(name) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/call_me_ruby.rb', line 53

def subscribed?(name)
  self.class.class_callbacks.include?(name) || callbacks.include?(name)
end