output.log

12:29 $ ./label_provider.rb
Object (label provider is incomplete for Puppet::Pops::Model::Factory)
12:29 $ 

traverse.rb

#! /usr/bin/env ruby
$LOAD_PATH.unshift '/opt/puppetlabs/puppet/lib/ruby/vendor_ruby/'
require 'puppet'
require 'puppet/parser'


# Following the pattern in http://puppet-on-the-edge.blogspot.com/2014/02/puppet-internals-polymorphic-dispatch.html
class LabelProvider

  def initialize
    @label_visitor = Puppet::Pops::Visitor.new(self, "label")
  end

  def label(o)
    @label_visitor.visit(o)
  end

  protected

  def label_ArithmeticExpression(o)
    "#{o.operator} Expression"   # i.e. '+ Expression', '- Expression' etc.
  end

  def label_String(o)
    "String"
  end

  def label_Regexp(o)
    "Regular Expression"
  end

  def label_Object(o)
    "Object (label provider is incomplete for #{o.class})"
  end
end

filename = '/Users/ben/Projects/binford2k-itemize/manifests/init.pp'
parser   = Puppet::Pops::Parser::EvaluatingParser.new
source   = Puppet::FileSystem.read(filename)
result   = parser.parse_string(source, filename)
provider = LabelProvider.new

# require 'pry'
# binding.pry

puts provider.label(result)