-- | Returns the derivation index of this extended private key without the
-- prime bit set.
xPrvChild :: XPrvKey -> Word32
xPrvChild k = clearBit (xPrvIndex k) 31
xPrvChild :: XPrvKey -> Word32
xPrvChild k = clearBit (xPrvIndex k) 31
xPrvChild k = clearBit (xPrvIndex k) 31