callback vs lambda

Question

Suppose I have the following code that I wish to refactor:

int toFuture()
{
  precalc();
  int calc = 5 * foobar_x() + 3;
  postcalc();
  return calc;
}

int toP         


        

Answer 1

One approach:

template
int perform_calc(CalcFuncT&& calcfunc)
{
    precalc();
    int const calc = std::forward(calcfunc)();
    postcalc();
    return calc;
}

int main()
{
    perform_calc([]{ return 5 * foobar_x() + 3; }); // toFuture
    perform_calc([]{ return 5 * foobar_y() - 9; }); // toPast
}