Hi, I have a struct adapted as a fusion sequence. My user inputs at runtime the index of the member she is interested in. Assuming all members are convertible to double, the only solution I found so far is: double f(unsigned index) { switch(index) { case 0: return boost::fusion::at_c<0>( sequence ); case 1: return boost::fusion::at_c<1>( sequence ); . case 6: return boost::fusion::at_c<6>( sequence ); } } To generate this: 1. 0 to fusion::result_of::size<Seq>::type::value - 1 is the range I want. 2. I can't use PP to generate the cases inside the switch 3. Can I generate an array of function pointers to the various at<>() functions and call the right one at runtime? I am basically looking for the runtime version of at_c. Regards,