# File lib_core/rucy/document.rb, line 322
    def set_virtual_alias(host, alias_path, orig_path)
      host += ':80'if (host !~ /:\d+$/)
      if (alias_path !~ %"^/") then
        raise "not a path: #{alias_path.inspect}"
      end
      if (orig_path !~ %"^/") then
        raise "not a path: #{orig_path.inspect}"
      end
      unless (@virtual_alias_map.include? host) then
        @virtual_alias_map[host] = Hash.new
      end
      @virtual_alias_map[host][alias_path] = orig_path
      nil
    end