lib/Reader.php
public function getDeserializerForElementName(string $name): callable
    {
        if (!array_key_exists($name, $this->elementMap)) {
            if ('{}' == substr($name, 0, 2) && array_key_exists(substr($name, 2), $this->elementMap)) {
                $name = substr($name, 2);
            } else {
                return ['Sabre\\Xml\\Element\\Base', 'xmlDeserialize'];
            }
        }

        $deserializer = $this->elementMap[$name];
        if (is_subclass_of($deserializer, 'Sabre\\Xml\\XmlDeserializable')) {
            return [$deserializer, 'xmlDeserialize'];
        }

        if (is_callable($deserializer)) {
            return $deserializer;
        }

        $type = gettype($deserializer);
        if ('string' === $type) {
            $type .= ' ('.$deserializer.')';
        } elseif ('object' === $type) {
            $type .= ' ('.get_class($deserializer).')';
        }
        throw new \LogicException('Could not use this type as a deserializer: '.$type.' for element: '.$name);
    }
public function getDeserializerForElementName(string $name): callable
    {
        if (!array_key_exists($name, $this->elementMap)) {
            if ('{}' == substr($name, 0, 2) && array_key_exists(substr($name, 2), $this->elementMap)) {
                $name = substr($name, 2);
            } else {
                return ['Sabre\\Xml\\Element\\Base', 'xmlDeserialize'];
            }
        }

        $deserializer = $this->elementMap[$name];
        if (is_subclass_of($deserializer, 'Sabre\\Xml\\XmlDeserializable')) {
            return [$deserializer, 'xmlDeserialize'];
        }

        if (is_callable($deserializer)) {
            return $deserializer;
        }

        $type = gettype($deserializer);
        if ('string' === $type) {
            $type .= ' ('.$deserializer.')';
        } elseif ('object' === $type) {
            $type .= ' ('.get_class($deserializer).')';
        }
        throw new \LogicException('Could not use this type as a deserializer: '.$type.' for element: '.$name);
    }
Returns the function that should be used to parse the element identified
by it's clark-notation name.