我正在尝试对模板类进行typedef接受默认的构造函数参数,但是我遇到了错误。
这很好用:
typedef TransientWriter<DDS::NetAcquire::MeasurandMetaData,
::NetAcquire::MeasurandMetaDataTypeSupport_var,
::NetAcquire::MeasurandMetaDataTypeSupportImpl,
::NetAcquire::MeasurandMetaDataDataWriter,
::NetAcquire::MeasurandMetaDataDataWriter_var,
::NetAcquire::MeasurandMetaDataDataReader,
::NetAcquire::MeasurandMetaDataDataReader_var> Writer;
但是,我希望此类通过构造函数采用默认的字符串参数。我试过了:
typedef TransientWriter<DDS::NetAcquire::MeasurandMetaData,
::NetAcquire::MeasurandMetaDataTypeSupport_var,
::NetAcquire::MeasurandMetaDataTypeSupportImpl,
::NetAcquire::MeasurandMetaDataDataWriter,
::NetAcquire::MeasurandMetaDataDataWriter_var,
::NetAcquire::MeasurandMetaDataDataReader,
::NetAcquire::MeasurandMetaDataDataReader_var>
(::NetAcquire::MeasurandMetaDataTopic) Writer;
这给了我一个奇怪的错误:
error: expected initializer before ‘Writer’
我也尝试过这样:
typedef TransientWriter<DDS::NetAcquire::MeasurandMetaData,
::NetAcquire::MeasurandMetaDataTypeSupport_var,
::NetAcquire::MeasurandMetaDataTypeSupportImpl,
::NetAcquire::MeasurandMetaDataDataWriter,
::NetAcquire::MeasurandMetaDataDataWriter_var,
::NetAcquire::MeasurandMetaDataDataReader,
::NetAcquire::MeasurandMetaDataDataReader_var>
Writer(::NetAcquire::MeasurandMetaDataTopic);
这给了我
error: typedef ‘JARSS::DDS::Object::NetAcquire::MeasurandMetaData::Writer’ is initialized (use decltype instead)
我会在这个typedef上出错吗?有什么建议我可以代替吗?
谢谢。
最佳答案
在C ++中无法做到这一点。
考虑创建一个新类,向TransientWriter<DDS::NetAcquire::MeasurandMetaData, ::NetAcquire::MeasurandMetaDataTypeSupport_var, ::NetAcquire::MeasurandMetaDataTypeSupportImpl, ::NetAcquire::MeasurandMetaDataDataWriter, ::NetAcquire::MeasurandMetaDataDataWriter_var, ::NetAcquire::MeasurandMetaDataDataReader, ::NetAcquire::MeasurandMetaDataDataReader_var>
的构造函数添加重载或创建工厂函数。