Boost C++ Libraries

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QVM: Quaternions, Vectors, Matrices

enable_if

#include <boost/qvm/enable_if.hpp>

namespace boost
{
    namespace qvm
    {
        using boost::enable_if;
        using boost::enable_if_c;
        using boost::lazy_enable_if;
        using boost::lazy_enable_if_c;
    }
}

These enable_if templates are used by Boost OVM to implement SFINAE/enable_if. By default, they refer to the implementation provided in the Boost enable_if library.