# File lib/gettext/tools/msgmerge.rb, line 93
        def merge
          result = GetText::PO.new

          @reference.each do |entry|
            id = [entry.msgctxt, entry.msgid]
            result[*id] = merge_definition(entry)
          end

          add_obsolete_entry(result) if @config.output_obsolete_entries?
          result
        end