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    <p>No. In a boost multi_index_container, the indices are coupled together as separate views of the same values. This is an important guarantee of boost multi_index_containers.</p> <blockquote> <p>"Boost.MultiIndex allows for the specification of multi_index_containers comprised of one or more indices with different interfaces to the same collection of elements" (<a href="http://www.boost.org/doc/libs/1_53_0/libs/multi_index/doc/tutorial/index.html" rel="nofollow">boost multi_index tutorial</a>).</p> </blockquote> <p>With two distinct sequenced&lt;> indices you can re-arrange the <em>order</em> in two different ways, but they must both contain all values.</p> <p>If you wish to view a subset of elements according to a boolean predicate (eg: value is odd), consider using <a href="http://www.boost.org/doc/libs/1_53_0/libs/iterator/doc/filter_iterator.html" rel="nofollow">boost::filter_iterator</a>. This does not attempt to <em>erase</em> values in the container but instead <em>skip</em> them during iteration.</p> <p>Alternatively, selection/filtering can be obtained by ordering, using a multi_index <a href="http://www.boost.org/doc/libs/1_53_0/libs/multi_index/doc/reference/ord_indices.html" rel="nofollow">ordered_non_unique</a> index with an appropriate <a href="http://www.boost.org/doc/libs/1_53_0/libs/multi_index/doc/tutorial/key_extraction.html" rel="nofollow">key extractor</a>. </p> <p>For example, an ordered_non_unique index based on a <a href="http://www.boost.org/doc/libs/1_53_0/libs/multi_index/doc/tutorial/key_extraction.html" rel="nofollow">key extractor</a>: <code>[](int i) { return i % 2; }</code> will place the odd and even values in distinct groups, so an iterator range to all odd values can be obtained using <a href="http://www.boost.org/doc/libs/1_53_0/libs/multi_index/doc/reference/ord_indices.html" rel="nofollow">equal_range</a>.</p>
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    1. POA multi-index where one index is a subset of the whole collection
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    1. POA multi-index where one index is a subset of the whole collection
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    1. COIt wouldn't have been predicate based and tagging each value with a deleted `bool` wouldn't have been possible as well. Thanks for providing a sourced answer (even if the question just celebrated its first birthday).
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    2. COThose requirements could be addressed via a customised multi index using [boost intrusive](http://www.boost.org/doc/libs/1_53_0/doc/html/intrusive.html). Using two or more [list hooks](http://www.boost.org/doc/libs/1_53_0/doc/html/intrusive/list.html) you can make one object participate in two or more sequences simultaneously.
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