Game loop variable time step code snippet - elapsed time not correctly computed

[titibandit]

In the snippet that introduces the variable time step:

double lastTime = getCurrentTime();
while (true)
{
  double current = getCurrentTime();
  double elapsed = current - lastTime;
  processInput();
  update(elapsed);
  render();
  lastTime = current;
}

the lastTime is computed at the wrong time: in that configuration, lastTime and current are computed directly after one another.
If I'm not mistaken, the correct snippet would be:

double lastTime = getCurrentTime();
while (true)
{
  double current = getCurrentTime();
  double elapsed = current - lastTime;
  lastTime = current;
  processInput();
  update(elapsed);
  render();
}

The next snippet after that gets it right.