Question

Why can’t the compiler figure out these template parameters? Is there a way to make it do so?

(I’m using Visual Studio 2010.)

template<typename T, typename TFunc>
void call(TFunc func) { func(T()); }

void myfunc(void *) { }

int main() { call(myfunc); }

Answer 1

T appears nowhere in the parameter list so T cannot be deduced from the function arguments. All types to be deduced must appear in deduced contexts in the parameter list. For example,

template <typename TReturn, typename TParameter>
void call(TReturn (*f)(TParameter))
{
    f(TParameter());
}