Runtime documentation for Ruby classes

rtdocumentation.rb

# NOTE: I just slapped this together as a proof of concept. Thread safety etc. is left to the reader.

module RTDocumentation

  def self.included(into)
    # method_added doesn't seem to work if mixed in
    into.send(:define_method, :method_added) do |name|
      if @_rtdoc_nextdoc
        @_rtdocs ||= {}
        @_rtdocs[name.to_s] = @_rtdoc_nextdoc
        doc nil
      end
    end
  end

  def doc_for(method)
    @_rtdocs ||= {}
    @_rtdocs[method.to_s]
  end

  private

  def doc(docstring)
    @_rtdoc_nextdoc = docstring
  end

end

class UnboundMethod
  def doc
    owner.doc_for(name)
  end
end

class Method
  def doc
    owner.doc_for(name)
  end
end

class Module
  include RTDocumentation
end

class Worf

  doc "Returns a true value if this worf is currently discommendated"
  def discommendated?
    true
  end

end

puts Worf.doc_for(:discommendated?)
puts Worf.instance_method(:discommendated?).doc
puts Worf.new.method(:discommendated?).doc