On 9/10/2013 10:54 AM, Antoine Pitrou wrote:
(also, I would intuitively expect the latest key to be held, not the first one, since that's what happens for values.)
I intuitively expected, and I think most often would want, the first key to be held. The reason being that I would except most often the initial insertion to be the canonical form.
Whichever way is adopted, I think even if you say it's implementation specific, people will end up relying on it in their code.