Zeuthen: Writing a C library, part 1

Zeuthen: Writing a C library, part 1

Posted Jul 7, 2011 12:08 UTC (Thu) by jwakely (subscriber, #60262)
In reply to: Zeuthen: Writing a C library, part 1 by gowen
Parent article: Zeuthen: Writing a C library, part 1

> In general, you can't return both results *and* error codes.

std::future<double> squerrt(double x)
{
  std::promise<double> p;
  if (x < 0)
    p.set_exception(copy_exception(std::domain_error("negative")));
  else
    p.set_value(sqrt(x));
  return p.get_future();
}

int main()
{
  double i = squerrt(-1).get();  // boom
}

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