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

I'd say you're refactoring from the wrong side:

struct CalcGuard {
  CalcGuard() { /* replaces precalc() */ }
  ~CalcGuard() { /* replaces postcalc() */ }
};

int toFuture()
{
  return CalcGuard(), calc = 5 * foobar_x() + 3;
}

int toPast()
{
  return CalcGuard(), calc = 5 * foobar_y() - 9;
}