protected function getEffect(array $coupons)
    {
        $discount = 0.00;
        /** @var CouponInterface $coupon */
        foreach ($coupons as $coupon) {
            $discount += $coupon->exec($this->facade);
        }

        return $discount;
    }
protected function getEffect(array $coupons)
    {
        $discount = 0.00;
        /** @var CouponInterface $coupon */
        foreach ($coupons as $coupon) {
            $discount += $coupon->exec($this->facade);
        }

        return $discount;
    }
protected function getEffect ( array $ coupons ) { $ discount = 0.00 ; /** @var CouponInterface $coupon */ foreach ( $ coupons as $ coupon ) { $ discount += $ coupon -> exec ( $ this -> facade ) ; } return $ discount ; }
Process given Coupon in order to get their cumulative effects

@param array $coupons CouponInterface to process

@return float discount
Process given Coupon in order to get their cumulative effects