[Boost-users] [MultiIndex] Indexing integers

Subject: [Boost-users] [MultiIndex] Indexing integers
From: Sensei (senseiwa_at_[hidden])
Date: 2014-07-09 06:06:08

Dear all,

I am experimenting with MultiIndex, and I am happy with my custom classes.

Now I am wondering, can I index integers without a custom class?

For instance, say we have a 32 bit unsigned integer, how can I index 
these with respect to the MSB or LSB? My first guess is using a union, 
something like

union uint32_u
{
     uint32_t data;

     uint16_t bits[2];
};

// define a multiply indexed set with indices by id and name
typedef boost::multi_index::multi_index_container<
     uint32_u,
     boost::multi_index::indexed_by<
         // sort by MSB
 
boost::multi_index::ordered_non_unique<boost::multi_index::member<employee, 
uint16_t, uint32_u.bits[0]>>,
         // sort by LSB
 
boost::multi_index::ordered_non_unique<boost::multi_index::member<employee, 
uint16_t, uint32_u.bits[1]>>,
     >
 > integer_set;

But I cannot obviously compile it.

Is there a way I can do this?

Thanks!