count
void count(_InputIter __first, _InputIter __last, const _Tp& __value,
count(_InputIter __first, _InputIter __last, const _Tp& __value) {
::count(const _Key& __k) const
enum { count = MaskOffset<(mask >> 1), ((mask >> 1) & 1UL)>::count + 1 };
enum { count = MaskOffset<(mask >> 1), ((mask >> 1) & 1UL)>::count + 1 };
enum { count = 0 };