# File lib/chef/provider/package/yum.rb, line 510
          def initialize
            # package name => [ RPMPackage, RPMPackage ] of different versions
            @rpms = Hash.new
            # package nevra => RPMPackage for lookups
            @index = Hash.new
            # provide name (aka feature) => [RPMPackage, RPMPackage] each providing this feature
            @provides = Hash.new
            # RPMPackages listed as available
            @available = Set.new
            # RPMPackages listed as installed
            @installed = Set.new
          end