class UserAgent::Browsers::InternetExplorer

def self.extend?(agent) 

def self.extend?(agent)
  agent.application &&
  agent.application.comment &&
  (agent.application.comment[1] =~ /MSIE/ ||
   agent.application.comment.join('; ') =~ /Trident.+rv:/)
end

def browser 

def browser
  "Internet Explorer"
end

def chromeframe

or as a separate product with a version
as of 4.0 it can declare itself versioned in a comment
Before version 4.0, Chrome Frame declared itself (unversioned) in a comment; 
def chromeframe
  cf = application.comment.include?("chromeframe") || detect_product("chromeframe")
  return cf if cf
  cf_comment = application.comment.detect { |c| c['chromeframe/'] }
  cf_comment ? UserAgent.new(*cf_comment.split('/', 2)) : nil
end

def compatibility_view? 

def compatibility_view?
  version == "7.0" && application.comment.detect { |c| c['Trident/'] }
end

def os 

def os
  OperatingSystems.normalize_os(application.comment.join('; ').match(/Windows NT [\d\.]+|Windows Phone (OS )?[\d\.]+/).to_s)
end

def platform 

def platform
  "Windows"
end

def version 

def version
  str = application.comment.join('; ')[/(MSIE\s|rv:)([\d\.]+)/, 2]
  Version.new(str)
end