Syntax failing with chain arrows and underscore in class name

[glennsarti]

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What You Are Seeing?

What is Expected?

How Did You Get This To Happen? (Steps to Reproduce)

# IIS Web Server
class web (
  String $site_path = 'E:\\Dev\\Website\\',
  String $website_name = 'new_website',
  String $app_pool_name = 'app_pool',
){
  windowsfeature{['Web-Server' , 'Web-Asp-Net45']:
    ensure => present
  }

  iis_application_pool { $app_pool_name:
    ensure                  => 'present',
    state                   =>' started',
    managed_pipeline_mode   => 'Integrated',
    managed_runtime_version => 'v4.0',
  }

  -> iis_site { $website_name:
    ensure          => 'started',
    physicalpath    => $site_path,
    applicationpool => $app_pool_name,
    require         => Iis_application_pool[$app_pool_name]
  }

  file { $site_path:
  ensure => 'directory'
  }
}

Note should also check ~> as well as ->