ARK's latest, hot off the press:

When Is It Safe to Move an Object Instead of Copying It?

by Andrew Koenig

From the article:

Last week, I introduced the idea of moving objects, and explained that moving an object is usually better than copying it if the original is not going to be used again. Now I'd like to explain how the compiler can figure out during compilation when to move objects instead of copying them.

As is so often the case with such problems, the obvious solution is wrong. Consider this code fragment: ...