Incorrect use of rvalue references and std::forward

[jonesmz]

See:

test/include/boost/test/data/monomorphic/grid.hpp

Line 96 in 11a8d37

grid( DataSet1&& ds1, DataSet2&& ds2 )

Which boils down to

template<typename DataSet1, typename DataSet2>
class grid {
    //! Constructor
    grid( DataSet1&& ds1, DataSet2&& ds2 )
    : m_ds1( std::forward<DataSet1>( ds1 ) )
    , m_ds2( std::forward<DataSet2>( ds2 ) )
    {}
};

Here DataSet1 and DataSet2, while template parameters to the class, are not template parameters to the function.

As a result, this formulation of the constructor always takes these two parameters as rvalue-reference.

This can be corrected in 3 ways

1. Take both parameters by value
2. Make the constructor a template function
3. Make additional constructors that represent the cross-product of const& and && for each parameter. In this case, resulting in 4 functions.

I see that this same mistake is done in more than one place, it's not only grid.hpp where it happens.