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Re: Concerned about the increasing reliance on XPath

• From: Stephen D Green <stephengreenubl@gmail.com>
• To: Michael Kay <mike@saxonica.com>
• Date: Mon, 9 May 2011 18:21:23 +0100

What would help would be another shorthand for "/*local-name()='foo'/...",
say something like "/{foo}/..." or some other parenthesis-based shorthand.

I remember how when pocket calculators came out there was the issue
of operator precedence. It was solved when they added brakets to the
key pad so you could make the precedence explicit (the implicit precedence
differed between calculators so the same calculation key-press sequence
was giving different results in different calculators). It's a bit
like that here.
Expecting people to know the default operator precedence for their
calculator before pressing keys would be unrealistic - and there the problem
was less severe than here, I think, because it was only more complex
calculation sequences where the problem was apparent; here it is simple
ones too.

----
Stephen D Green



On 9 May 2011 17:10, Michael Kay <mike@saxonica.com> wrote:
> On 09/05/2011 16:43, Stephen D Green wrote:
>>
>> I tried to think of a way to write the XPath expression so
>> it gives the same result whatever the version of XPath
>
> You can write
>
> /example:a/@version-id = 0.4
>
> or
>
> /example:a/@version-id = '0.4'
>
> depending on which you mean [*], in both cases using the API of the
> processor to ensure that prefix "example" is bound to namespace URI
> "http://www.example.com".
>
> Writing it in a way that doesn't depend on any namespace bindings set up via
> the API is much harder - XPath is designed on the assumption that the
> bindings will be set up externally, and you're going against the grain if
> you don't want to do that.
>
> Michael Kay
> Saxonica
>
> [*] the first will also match version-id="0.40", the second won't. Yes,
> XPath is not a language designed for people who find such fine distinctions
> irritating - the "do what I meant, not what I said" brigade.
>
>
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• Follow-Ups:
  • Re: Concerned about the increasing reliance on XPath
    • From: Philip Fearon <pgfearo@googlemail.com>
  • Re: Concerned about the increasing reliance on XPath
    • From: Andrew Welch <andrew.j.welch@gmail.com>
  • Re: Concerned about the increasing reliance on XPath
    • From: Stephen D Green <stephengreenubl@gmail.com>

• References:
  • Concerned about the increasing reliance on XPath
    • From: "Costello, Roger L." <costello@mitre.org>
  • Re: Concerned about the increasing reliance on XPath
    • From: Stephen D Green <stephengreenubl@gmail.com>
  • Re: Concerned about the increasing reliance on XPath
    • From: David Carlisle <davidc@nag.co.uk>
  • Re: Concerned about the increasing reliance on XPath
    • From: Stephen D Green <stephengreenubl@gmail.com>
  • Re: Concerned about the increasing reliance on XPath
    • From: Michael Kay <mike@saxonica.com>