code: function (parsed){
          var self = this,
              opt = this.opt,
              src = opt.source,
              root = opt.root,
              csspath = parsed.csspath,
              hash = parsed.hash,
              host = parsed.host,
              search = parsed.search,
              md5 = parsed.md5,
              ext = parsed.ext,
              name = parsed.name,
              version = parsed.version,
              ret;
  
          root = this.normalize_path(root);
          name = mod_path.relative(src,name);
          name = mod_path.join(root,name);
          ret = (host||"")+name;
          if(!opt.no_version){
              ret+= "." + version;
          }
  
          if(opt.md5){
              ret+= "." + md5;
          }
  
          ret += ext;
          search && (ret += search);
          hash && (ret += hash);
          return ret;
      }
docs: 连接器，处理相对图片路径的各部分，将之拼装为目标格式
  @param  {[type]} parsed {host,ext,name,version}
  @return {String}        [description]