// returns higher n bits of b, which n is is the bit index of the lowest byte
returns higher n bits of b, which n is is the bit index of the lowest byte
// returns higher n bits of b which n is is the bit index of the lowest byte
func (p BitIndex) Mask(b byte) byte {
	bits := p.BitPos()
	if bits == 7 {
		return b
	}
	if bits == 0 {
		return 0
	}
	sh := 7 - bits
	bb := b >> sh
	bb = bb << sh
	return bb
}
func ( p BitIndex ) Mask ( b byte ) byte { bits := p . BitPos ( ) if bits == 7 { return b } if bits == 0 { return 0 } sh := 7 - bits bb := b >> sh bb = bb << sh return bb }
returns higher n bits of b, which n is is the bit index of the lowest byte
returns higher n bits of b which n is is the bit index of the lowest byte