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Re: Extracting values from xml file using php/xpath/namespace/simplexml/

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On 9/7/2014 5:57 AM, Thomas 'PointedEars' Lahn wrote:
> Denis McMahon wrote:
> 
>> On Fri, 05 Sep 2014 04:08:09 +0200, Christoph M. Becker wrote:
>>> Jerry Stuckle wrote:
>>>> On 9/4/2014 5:21 PM, Thomas 'Pointed Head' Lahn wrote:
>>>>> Jerry Stuckle wrote:
>>>> His code will detect the change in the markup.  Yours will not, because
>>>> you are not using the full XPath.  And once again - yours can fail if
>>>> the XML happens to have multiple (but different) XPaths with the same
>>>> identifiers.  The Ops will not.
>>>
>>> "Mutitple (but different) XPaths"?  Do you mean multiple (but different)
>>> XPath expressions?
>>
>> No
>>
>> Jerry is trying to point out to tpel-troll that if you use a partial xpath
>> instead of a fully qualified xpath to match data in an xml document,
>> there is a risk that if the same partial xpath matches one or more
>> unwanted elements as well as the wanted element(s), the unwanted element
>> (s) will end up as part of the selection.
> 
> If he would have, this would be showing that he does not understand XPath.
> As you assume he did, you clearly do not understand XPath.
> 
> An XPath query always matches all elements that match that path.  In a XML 
> document
> 
>   <foo>
>     <bar id="baz" />
>     <bar id="bla" />
>   </foo>
> 
> the path '/foo/bar' matches <bar id="baz" /> *and* <bar id="bla" />.
> 
> Therefore, the return value of SimpleXMLElement::xpath() is *always* an 
> array, unless the query is syntactically in error, in which case the return 
> value is FALSE.
> 
> As for “unwanted elements”, it is a fallacy to assume that if the structure 
> of the XML document changes, a more general query *must* return unwanted 
> elements.  For example, if the structure changes to
> 
>   <foo>
>     <bars>
>       <bar id="baz" />
>       <bar id="bla" />
>     </bars>
>   </foo>
> 
> (which makes sense structurally) the result for the more general XPath query 
> './/bar' will still contain only wanted elements, namely still only <bar 
> id="baz" /> and <bar id="bla" />.  It could be further refined by using 
> /bars[1] as *context node* (using '.' in the path), referring only to nodes 
> *below* that node in the hierarchy of the data structure.  This is what I 
> referred to with flexibility.  
> 
> IOW: Using the full XPath path is _not_ always the best approach.
> 

Once again you're as full of crap as your code is full of holes.  But I
should know better than to try to teach the troll.  It's like trying to
teach a pig to sing.

-- 
==================
Remove the "x" from my email address
Jerry Stuckle
jstucklex@attglobal.net
==================

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Extracting values from  xml file using php/xpath/namespace/simplexml/ ofuuzo@gmail.com - 2014-08-13 04:02 -0700
  Re: Extracting values from  xml file using php/xpath/namespace/simplexml/ Jerry Stuckle <jstucklex@attglobal.net> - 2014-08-13 09:25 -0400
    Re: Extracting values from  xml file using php/xpath/namespace/simplexml/ ofuuzo@gmail.com - 2014-08-14 03:29 -0700
      Re: Extracting values from  xml file using php/xpath/namespace/simplexml/ Jerry Stuckle <jstucklex@attglobal.net> - 2014-08-14 10:06 -0400
      Re: Extracting values from  xml file using php/xpath/namespace/simplexml/ Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-08-17 19:43 +0200
        Re: Extracting values from  xml file using php/xpath/namespace/simplexml/ Jerry Stuckle <jstucklex@attglobal.net> - 2014-08-17 15:21 -0400
          Re: Extracting values from  xml file using php/xpath/namespace/simplexml/ Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-08-17 23:41 +0200
            Re: Extracting values from  xml file using php/xpath/namespace/simplexml/ Jerry Stuckle <jstucklex@attglobal.net> - 2014-08-17 18:57 -0400
              Re: Extracting values from  xml file using php/xpath/namespace/simplexml/ Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-09-03 23:10 +0200
                Re: Extracting values from  xml file using php/xpath/namespace/simplexml/ Jerry Stuckle <jstucklex@attglobal.net> - 2014-09-03 20:11 -0400
                Re: Extracting values from  xml file using php/xpath/namespace/simplexml/ "Christoph M. Becker" <cmbecker69@arcor.de> - 2014-09-04 02:42 +0200
                Re: Extracting values from  xml file using php/xpath/namespace/simplexml/ Jerry Stuckle <jstucklex@attglobal.net> - 2014-09-03 21:57 -0400
                Re: Extracting values from  xml file using php/xpath/namespace/simplexml/ Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-09-04 23:21 +0200
                Re: Extracting values from  xml file using php/xpath/namespace/simplexml/ Jerry Stuckle <jstucklex@attglobal.net> - 2014-09-04 20:43 -0400
                Re: Extracting values from  xml file using php/xpath/namespace/simplexml/ "Christoph M. Becker" <cmbecker69@arcor.de> - 2014-09-05 04:08 +0200
                Re: Extracting values from  xml file using php/xpath/namespace/simplexml/ Denis McMahon <denismfmcmahon@gmail.com> - 2014-09-05 02:50 +0000
                Re: Extracting values from  xml file using php/xpath/namespace/simplexml/ Jerry Stuckle <jstucklex@attglobal.net> - 2014-09-05 08:24 -0400
                Re: Extracting values from  xml file using php/xpath/namespace/simplexml/ Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2014-09-07 11:57 +0200
                Re: Extracting values from  xml file using php/xpath/namespace/simplexml/ Jerry Stuckle <jstucklex@attglobal.net> - 2014-09-07 09:54 -0400
                Re: Extracting values from  xml file using php/xpath/namespace/simplexml/ "M. Strobel" <sorry_no_mail_here@nowhere.dee> - 2014-09-07 23:53 +0200

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