LiquidContext::variable PHP Метод

    public function variable($key)
    {
        /* Support [0] style array indicies */
        if (preg_match("|\\[[0-9]+\\]|", $key)) {
            $key = preg_replace("|\\[([0-9]+)\\]|", ".\$1", $key);
        }
        $parts = explode(LIQUID_VARIABLE_ATTRIBUTE_SEPARATOR, $key);
        $object = $this->fetch(array_shift($parts));
        if (is_object($object)) {
            if (!method_exists($object, 'toLiquid')) {
                $object = (array) $object;
            } else {
                $object = $object->toLiquid();
            }
        }
        if (!is_null($object)) {
            while (count($parts) > 0) {
                if ($object instanceof LiquidDrop) {
                    $object->setContext($this);
                }
                $nextPartName = array_shift($parts);
                if (is_array($object)) {
                    // if the last part of the context variable is .size we just return the count
                    if ($nextPartName == 'size' && count($parts) == 0 && !array_key_exists('size', $object)) {
                        return count($object);
                    }
                    if (array_key_exists($nextPartName, $object)) {
                        $object = $object[$nextPartName];
                    } else {
                        return null;
                    }
                } elseif (is_object($object)) {
                    if ($object instanceof LiquidDrop) {
                        // if the object is a drop, make sure it supports the given method
                        if (!$object->hasKey($nextPartName)) {
                            return null;
                        }
                        // php4 doesn't support array access, so we have
                        // to use the invoke method instead
                        $object = $object->invokeDrop($nextPartName);
                    } elseif (method_exists($object, LIQUID_HAS_PROPERTY_METHOD)) {
                        if (!call_user_method(LIQUID_HAS_PROPERTY_METHOD, $object, $nextPartName)) {
                            return null;
                        }
                        $object = call_user_method(LIQUID_GET_PROPERTY_METHOD, $object, $nextPartName);
                    } else {
                        // if it's just a regular object, attempt to access a property
                        if (!property_exists($object, $nextPartName)) {
                            return null;
                        }
                        $object = $object->{$nextPartName};
                    }
                }
                if (is_object($object) && method_exists($object, 'toLiquid')) {
                    $object = $object->toLiquid();
                }
            }
            return $object;
        } else {
            return null;
        }
    }