code: function registerProcessor(encoding, processor) {
    if (!processor || !encoding) {
      return;
    }
    if (typeof processor === 'function') {
      defaultProcessors[encoding] = processor;
      return true;
    }
    else if (typeof processor === 'string' && processor) {
      if (fs.existsSync(processor)) {
        return registerProcessor(
          encoding,
          scope.buildProcessor(fs.readFileSync(processor))
        );
      }
      else {
        return registerProcessor(
          encoding,
          scope.buildProcessor(processor)
        );
      }
    }
  }
docs: 注册默认处理器
  
  @param {string} encoding 编码名称
  @param {Function|string} processor 处理函数