[boost] Fusion question- equality of tuples vs mpl sequences

/// Testing remove { typedef vector<Y, char, long, X, bool, double> mpl_vec; BOOST_TEST((fusion::remove(mpl_vec(), identity<X>()) == tuple<Y, char, long, bool, double>())); BOOST_TEST((fusion::remove(mpl_vec(), identity<Y>()) == tuple<char, long, X, bool, double>())); BOOST_TEST((fusion::remove(mpl_vec(), identity<long>()) == tuple<Y, char, X, bool, double>())); } My question is how does the above WORK? What caught my attention is the char,long,bool, and double have undefined values in them. Is it that when performing a ==, if one is comparing a mpl sequence the equality is based solely on TYPE? (is that what is going on?) Thanks, Brian :)