Passing the template Variadic argument package to the following function
In my debug code, I've done my own rework of printf () (classic).
template<typename T, typename ...Args>
void Printf(wchar_t const * message, T value, Args ...args);
void Printf(wchar_t const * message);
void Printf();
It uses variation patterns and works great.
Now I want to use Printf () in several functions that will take almost the same arguments, but execute Printf () in different ways. Here is one of the Printf () client functions
template<typename ...Args>
void Debug::Line(unsigned int in_tabs, wchar_t const * in_string, Args...in_args){
for (unsigned int i = 0; i < in_tabs; ++i)
Tab();
Printf(in_string, in_args...);
NewLine();
}
As soon as I start using this construct, I start getting UNRESOLVED linker errors
error LNK2019: unresolved external symbol "public: static void __cdecl Nerv::Debug::Line<>(unsigned int,wchar_t *)" (??$Line@$$$V@Debug@Nerv@@SAXIPA_W@Z) referenced in function "public: void __thiscall Nerv::UI::NervUIRect::DebugRect(void)" (?DebugRect@NervUIRect@UI@Nerv@@QAEXXZ)
error LNK2019: unresolved external symbol "public: static void __cdecl Nerv::Debug::Line<int,int>(unsigned int,wchar_t *,int,int)" (??$Line@HH@Debug@Nerv@@SAXIPA_WHH@Z) referenced in function "public: void __thiscall Nerv::UI::NervUIRect::DebugRect(void)" (?DebugRect@NervUIRect@UI@Nerv@@QAEXXZ)
This is strange to me, because I first tested this construction on a simpler case and it worked great.
template<typename T,typename...Ts>
void Printf(T value,Ts...args){
OutputDebugString(value);
Printf(args...);
}
void Printf(){
}
template<typename...Args>
void UsePrintf(Args...args){
Printf(args...);
}
The difference from the simple case is that all these functions (which don't work) are static members of the Debug class and that there are some additional function arguments. So how am I supposed to do this?
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