Bitwise AND the value of the specified rhs array with the value of this array (retaining the results), and return a non‐`const` reference to this object. The length of the result will be the maximum of the lengths of this object and rhs, where any most‐significant bits that are represented in one of the two but not the other will be set to 0. Note that a &= b; will result in the same value of a as a = a & b;.