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QVM: Quaternions, Vectors, Matrices


#include <boost/qvm/deduce_quat.hpp>

namespace boost
    namespace qvm
        template <class Q>
        struct deduce_quat
            typedef Q type;


is_quat<Q>::value is true.


  • is_quat<deduce_quat<Q>::type>::value must be true
  • deduce_quat<Q>::type must be copyable

This template is used by Boost QVM whenever it needs to deduce a copyable quaternion type from a single user-supplied function parameter of quaternion type. Note that Q itself may be non-copyable.

The main template definition returns Q, which means that it is suitable only for copyable quaternion types. Boost QVM also defines (partial) specializations for the non-copyable quaternion types it produces. Users can define other (partial) specializations for their own types.

A typical use of the deduce_quat template is for specifying the preferred quaternion type to be returned by the generic function template overloads in Boost QVM depending on the type of their arguments.