> Template libraries that have to deal with stuff that could throw vs couldn't end up with lots of nearr duplicate code, twice as much needed test coverage, and

> Template libraries that have to deal with stuff that could throw vs couldn't end up with lots of nearr duplicate code, twice as much needed test coverage, and/or less efficiency if you just cover the could-throw case. And you will still probably get it wrong. what are you referring to ? I have never seen template libraries having to do anything particular wrt to exceptions. If you want to throw just throw, that's the point.