alias_method_is_not_def.rb

# Demonstration showing that
#
#   alias_method :bar, :foo
#
# is not equivalent to
#
#   def bar
#     foo
#   end

class Entity
  def foo
    p :entity_foo
  end
end

class Thing < Entity
  alias_method :bar, :foo
end

class Person < Thing
  def foo
    p :person_foo
    super
  end

  def bar
    p :person_bar
    super
  end
end

Person.new.bar
# :person_bar
# :entity_foo


# -----------------------------------

class Entity
  def foo
    p :entity_foo
  end
end

class Thing < Entity
  def bar
    p method(:foo)
    foo
  end
end

class Person < Thing
  def foo
    p :person_foo
    super
  end

  def bar
    p :person_bar
    super
  end
end

Person.new.bar
# :person_bar
# #<Method: Person#foo>
# :person_foo
# :entity_foo