protected function andEvaluator(array $conditions, callable $leafEvaluator)
    {
        $sawNullResult = false;
        foreach ($conditions as $condition) {
            $result = $this->evaluate($condition, $leafEvaluator);
            
            if ($result === false) {
                return false;
            }

            if ($result === null) {
                $sawNullResult = true;
            }
        }

        return $sawNullResult ? null : true;
    }
protected function andEvaluator(array $conditions, callable $leafEvaluator)
    {
        $sawNullResult = false;
        foreach ($conditions as $condition) {
            $result = $this->evaluate($condition, $leafEvaluator);
            
            if ($result === false) {
                return false;
            }

            if ($result === null) {
                $sawNullResult = true;
            }
        }

        return $sawNullResult ? null : true;
    }
protected function andEvaluator ( array $ conditions , callable $ leafEvaluator ) { $ sawNullResult = false ; foreach ( $ conditions as $ condition ) { $ result = $ this -> evaluate ( $ condition , $ leafEvaluator ) ; if ( $ result === false ) { return false ; } if ( $ result === null ) { $ sawNullResult = true ; } } return $ sawNullResult ? null : true ; }
Evaluates an array of conditions as if the evaluator had been applied
to each entry and the results AND-ed together.

@param array    $conditions    Audience conditions list.
@param callable $leafEvaluator Method to evaluate leaf condition.

@return null|boolean True if all the operands evaluate to true.
False if a single operand evaluates to false.
Null if conditions couldn't be evaluated.
Evaluates an array of conditions as if the evaluator had been applied to each entry and the results AND - ed together .