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rgb_pixel<24> foo;    
foo.channel<channel_name::R>(63);

rgb_pixel<24> foo;    
foo.channel<channel_name::R,channel_name::G,channel_name::B>(63,31,47);

// sets the integer channel value by name
template<typename Name>
constexpr inline void channel(typename channel_by_index<channel_index_by_name<Name>::value>::int_type value) {
    constexpr const int index = channel_index_by_name<Name>::value;
    channel<index>(value);
}
// sets the integer channel values by name
template<typename Name1, typename Name2>
constexpr inline void channel(typename channel_by_index<channel_index_by_name<Name1>::value>::int_type value1,
                                typename channel_by_index<channel_index_by_name<Name2>::value>::int_type value2) {
    constexpr const int index1 = channel_index_by_name<Name1>::value;
    channel<index1>(value1);
    constexpr const int index2 = channel_index_by_name<Name2>::value;
    channel<index2>(value2);
}
// sets the integer channel values by name
template<typename Name1, typename Name2, typename Name3>
constexpr inline void channel(typename channel_by_index<channel_index_by_name<Name1>::value>::int_type value1,
                                typename channel_by_index<channel_index_by_name<Name2>::value>::int_type value2,
                                typename channel_by_index<channel_index_by_name<Name3>::value>::int_type value3) {
    constexpr const int index1 = channel_index_by_name<Name1>::value;
    channel<index1>(value1);
    constexpr const int index2 = channel_index_by_name<Name2>::value;
    channel<index2>(value2);
    constexpr const int index3 = channel_index_by_name<Name3>::value;
    channel<index3>(value3);
}