protected function equiv($a, $b): bool
    {
        if (\is_array($a) && \is_scalar($b)) {
            return \in_array($b, $a);
        }

        if (\is_array($b) && \is_scalar($a)) {
            return \in_array($a, $b);
        }

        return ($a == $b);
    }
protected function equiv($a, $b): bool
    {
        if (\is_array($a) && \is_scalar($b)) {
            return \in_array($b, $a);
        }

        if (\is_array($b) && \is_scalar($a)) {
            return \in_array($a, $b);
        }

        return ($a == $b);
    }
protected function equiv ( $ a , $ b ) : bool { if ( \ is_array ( $ a ) && \ is_scalar ( $ b ) ) { return \ in_array ( $ b , $ a ) ; } if ( \ is_array ( $ b ) && \ is_scalar ( $ a ) ) { return \ in_array ( $ a , $ b ) ; } return ( $ a == $ b ) ; }
Are two values equivalent.

For the purposes of this class, equivalence is defined as:
- When the two variables have equal values;
- When the two variables have identical values;
- When one variable's value is contained in the other variable's value,
where any one of the variables is a set/array.

@param mixed $a
@param mixed $b
Are two values equivalent .