C++ template - type/value mismatch at argument -

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• c++ type/value mismatch @ argument 1 in template parameter list 1 answer

i getting these errors,

type/value mismatch @ argument 1 in template parameter list ‘template class sasenginequeue’

type/value mismatch @ argument 2 in template parameter list ‘template class sasenginequeue’

but if use template arguments of sasenginequeue class std::string, ok, code below if use std::vector, there errors. why?

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class sasengine{ private:     unsigned char addr;     sasenginequeue<std::vector, std::vector> sasq;     sastcp_ip sastransport; }; 

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template<typename exception_t, typename lp_t> class sasenginequeue{ public:     threadsafequeue<exception_t> exceptionq;     threadsafequeue<lp_t> lpcmdq;     threadsafequeue<lp_t> lprspq; }; 

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template<typename msgtype> class threadsafequeue{ protected:     queue<msgtype> threadsafeq;     mutex mu;  public:     int get(msgtype& msg);     void push(msgtype msg);     void pop(); }; 

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template<typename msgtype> int threadsafequeue<msgtype>::get(msgtype& msg){     lock_guard<mutex> automutex(mu);      if(threadsafeq.empty()){         //empty queue         return -1;     }     msg = threadsafeq.front();     return 0; }  template<typename msgtype> void threadsafequeue<msgtype>::push(msgtype msg){     lock_guard<mutex> automutex(mu);     threadsafeq.push(msg); }  template<typename msgtype> void threadsafequeue<msgtype>::pop(){     lock_guard<mutex> automutex(mu);     threadsafeq.pop(); }  template int threadsafequeue<std::vector>::get(std::vector& msg); template void threadsafequeue<std::vector>::push(std::vector msg); template void threadsafequeue<std::vector>::pop(); template int threadsafequeue<std::string>::get(std::string& msg); template void threadsafequeue<std::string>::push(std::string msg); template void threadsafequeue<std::string>::pop(); 

you should point out error occurring - makes lot easier people trying answer.

anyway, issue while std::string type (specifically, typedef std::basic_string<char>), std::vector isn't. it's template, , need specify type vector contains, e.g. std::vector<int>.

you might want make work vector - unfortunately, doesn't work, because explicit instantiations have specify concrete type.