[section:rotate Range Algorithm - rotate] [heading Prototype] `` template ForwardRange& rotate(ForwardRange& rng, typename range_iterator::type middle); template const ForwardRange& rotate(const ForwardRange& rng, typename range_iterator::type middle); `` [heading Description] `rotate` rotates the elements in a range. It exchanges the two ranges `[begin(rng), middle)` and `[middle, end(rng))`. Returns a reference to `rng`. [heading Definition] Defined in the header file `boost/range/algorithm/rotate.hpp` [heading Requirements] * `ForwardRange` is a model of the __forward_range__ Concept. * `ForwardRange` is mutable. [heading Precondition:] * `[begin(rng), middle)` is a valid range. * `[middle, end(rng))` is a valid range. [heading Complexity] Linear. At most `distance(rng)` swaps are performed. [endsect]