anchor.diff:  #
   class <%= metadata.name %> (
   
  -  $ensure                    = 'present',
  -  $version                   = undef,
  -
     $package_name              = $<%= metadata.name %>::params::package_name,
  +  $package_ensure            = 'present',
   
     $service_name              = $<%= metadata.name %>::params::service_name,
     $service_ensure            = 'running',
  
positive.code: 
    # Class variables validation and management
  
    validate_re($ensure, ['present','absent'], 'Valid values: present, absent.')
    validate_bool($service_enable)
    validate_bool($config_dir_recurse)
    validate_bool($config_dir_purge)
  
negative.code: 
    if $<%= metadata.name %>::package_name {
      package { $<%= metadata.name %>::package_name:
        ensure   => $<%= metadata.name %>::package_ensure,
      }
    }
  
  