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Subject: Re: [PHP-DEV] SimpleXML's atXPath method
From: rowan.collins@gmail.com (Rowan Collins)

On 06/01/2017 14:03, Willian Veiga wrote:
> Hello,
>
> What do you think about a new method, called atXPath, that would return a
> single SimpleXMLElement?
>
> Details:
>
> https://github.com/php/php-src/pull/1717
> https://bugs.php.net/bug.php?id=45201
>
> Thank you, Willian.
>

My first thought on this was "what does the 'at' mean?" I see now that 
it's copied from another library, but "atXPath" really doesn't make me 
think "xpath for single element".

My second thought is that this feature is actually no longer needed. The 
original feature request was to avoid the need for an intermediate 
variable when you know you're getting back one result:

$firstresult=$xml->xpath('element[@called="XYZ"]');
$secondresult=$firstresult[0]->xpath('child[@named="ABC"]');
$finalresult=$secondresult[0];

But in all versions of PHP since 5.4 you can simply add the [0] on the 
end of the function call anyway:

$finalresult=$xml->xpath('element[@called="XYZ"]')[0]->xpath('child[@named="ABC"]')[0];

Like the original proposal for an extra parameter, this extends to 
selecting whichever result you want, as long as you're sure it exists.

Example: https://3v4l.org/1k9rk

If you don't know for sure that there will be enough results, then 
chaining will give an error either way, and this isn't really any 
different from any other method that might or might not return the 
expected object.

Regards,

-- 
Rowan Collins
[IMSoP]