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    <p><strong>Update:</strong> Using a <code>std::unique_ptr</code> as a holder for the container is the canonical generic solution - simply don't move the container, just transfer the ownership and swap the iterators. As you already said you can special-case this as an optimization, although I'd expect the generic solution to be also quite efficient and I'd only accept more complexity (aka bug-potential) to the code after proving that it's a real performance win for your use-case.</p> <p>I'll leave the former answer below for future readers: Read it and the comments to see why other solutions are not really working and in which cases they cause trouble.</p> <hr> <p>The obvious way to update the iterator would be:</p> <pre><code>Container c = ...; Container::iterator it = ...; const auto d = std::distance( c.begin(), it ); Container n = std::move(c); it = n.begin(); std::advance( it, d ); </code></pre> <p>which is generally linear, but constant when the iterator is a random access iterator.</p> <p>Since you probably don't want to do that, you have two options which should help: Either default construct the new container and use <code>swap</code> without invalidating the iterators or put the container into a <code>std::unique_ptr</code> and move that instead.</p> <p>The first approach (<code>swap</code>) requires both instances to have the container instance and this might be a bit larger than the simple, single pointer stored inside a <code>std::unique_ptr</code>. When you move your instances around very often, the <code>std::unique_ptr</code>-based approach seems preferable to me, although each access requires one more pointer indirection. Judge (and measure) for yourself what fits best in your case.</p>
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    1. COOr just `it = std::next(n.begin(), d)` for conciseness.
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    2. COOwch, I think I'd rather pay dynamic allocation than a linear price.
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    3. CO@DeadMG Good choice :)
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