Ruby Fu

The super keyword is pretty sweet. It remembers the context under which it was used, even when you call an alias of the containing method. Example:

class X
  def method
    "got it"
  end
end
class Y < X
  def method
    "#{super}!"
  end
end
class Z < Y
  alias_method :original_method, :method
  def method
    "you #{original_method}"
  end
end

X.new.method # <= "got it"
Y.new.method # <= "got it!"
Z.new.method # <= "you got it!"

This behavior gives alias_method real flexibility when used to modify behaviors by composing method chains to pre-defined methods. I was first surprised by this behavior, but it was a pleasant surprise as it meant I didn't have to worry about 'super' suddenly referring to something else when delegating to aliased methods.

Labels: class, inheritance, method, ruby, super