# File lib/cgikit/declaration.rb, line 21
    def merge_source( source, destination )
      source.each do |decname, dechash|
        if destination.key?(decname) then
          dechash.each do |attrname, attrvalue|
            unless destination[decname].key?(attrname) then
              destination[decname][attrname] = attrvalue
            end
          end
        else
          destination[decname] = dechash
        end
      end
    end