Thursday 14 June 2007

C++ using templatised params in typedef and general struggling

Trying to do something completely perfectly in C++ but it's becoming an epic struggle. Templatised things must be kept in a list, processed by template class (invoked two different threads). But the templatisation must be exposed to interface in and out of class.

Just one of numerous problems seem to be with a typedef of a hash map of templatised types ...  The kind of typedef used here works if the HashMap params aren't templatised params. I might be missing some relatively basic C++ template knowledge or, well the why doesn't it just do what I mean! :'(

template<typename QIdType, typename SeqType>
class CRetxLink
{

   typedef struct retx_data
   ...
      SeqType                    m_retx_seq_no;
   ...
   } retx_data_t;

typedef dts::HashMap<QIdType, retx_data_t*> HashTypeData;
boost::shared_ptr<HashTypeData> p_retx_list;

// compiler doesn't like this:
HashTypeData::iterator iterData = p_retx_list->begin();


// e.g. this is okay outside of class
typedef struct retx_data
   ...
      unsigned int                    m_retx_seq_no;
   ...
   } retx_data_t;

typedef dts::HashMap<unsigned int, retx_data_t*> HashTypeData;


Need to go back and start with the basics again .....


// essentially a generic interface to the templatized classes would be a start.

#include <string>
#include <iostream>

//g++ ~/c/templateInterface.cpp -o ~/c/templateInterface

class CTempInterface
{
public:
CTempInterface()
{
};

~CTempInterface()
{
};

virtual void Method()
{
printf("Method %s\n", __FUNCTION__);
}

};

template<typename T>
class TTemp : public CTempInterface
{
public:
TTemp()
{
};

~TTemp()
{
};

void Method()
{
printf("Method %s\n", __FUNCTION__);
std::cout << "two: " << thingywotsit << "\n";
}

T thingywotsit;

};


int main()
{
TTemp<int> tt_i;
TTemp<std::string> tt_s;

//TTemp &p;
CTempInterface *p;

p = &tt_i;
p->Method();

p = &tt_s;
p->Method();
}

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