suffixes

# File lib/rubygems.rb, line 881
  def self.suffixes
    @suffixes ||= ['',
                   '.rb',
                   *%(DLEXT DLEXT2).map { |key|
                     val = RbConfig::CONFIG[key]
                     next unless val and not val.empty?
                     ".#{val}"
                   }
                  ].compact.uniq
  end