Writing functions in Ruby: Documenting Ruby functions

Puppet Strings, a free documentation tool for Puppet, can extract code details and specially-formatted comments to build documentation pages for functions. This page describes the proper formatting to make your comments work well with Strings.

Note: This is one of several pages describing the Ruby functions API. Before reading it, make sure you understand the overview of this API and how to define function signatures.


Full content for this page is coming soon. In the meantime, the following examples show how to format comments in two situations: a function with two explicit signatures, and a function with an automatic signature.

# Subtracts two things.
Puppet::Functions.create_function(:subtract) do
  # Subtracts two integers.
  # @param x The first integer.
  # @param y The second integer.
  # @return [Integer] Returns x - y.
  # @example Subtracting two integers.
  #   subtract(5, 1) => 4
  dispatch :subtract_ints do
    param 'Integer', :x
    param 'Integer', :y

  # Subtracts two arrays.
  # @param x The first array.
  # @param y The second array.
  # @return [Array] Returns x - y.
  # @example Subtracting two arrays.
  #   subtract([3, 2, 1], [1]) => [3, 2]
  dispatch :subtract_arrays do
    param 'Array', :x
    param 'Array', :y

  def subtract_ints(x, y)
    x - y

  def subtract_arrays(x, y)
    x - y
# Says goodbye (in the master's output).
Puppet::Functions.create_function(:goodbye) do
  # @param [String] name The name of the person to say goodbye to.
  # @return [Undef]
  # @example Saying goodbye is hard to do.
  #   goodbye('world') => 'goodbye world'
  def goodbye(name)
    puts "goodbye #{name}!"