Re: XPath for expressing contiguous elements?

Sorry, this works only on Roger's examples ...

> Here is one without any negation:
>
> /*/A[preceding-sibling::A][following-sibling::A]
>            [preceding-sibling::*[1][self::A]]
>            [following-sibling::*[1][self::A]]
> and true()



On Mon, May 1, 2017 at 8:06 AM, Dimitre Novatchev <dnovatchev@xxxxxxxxx> wrote:
> Here is one without any negation:
>
> /*/A[preceding-sibling::A][following-sibling::A]
>            [preceding-sibling::*[1][self::A]]
>            [following-sibling::*[1][self::A]]
> and true()
>
>
> On Mon, May 1, 2017 at 7:21 AM, Michael Kay mike@xxxxxxxxxxxx
> <xsl-list-service@xxxxxxxxxxxxxxxxxxxxxx> wrote:
>> not(*[not(self::A)][following-sibling::A][preceding-sibling::A])
>>
>> returns true if and only if there is no non-A element that is both preceded and followed by an A element, which I think is equivalent to your expression and rather simpler.
>>
>> Michael Kay
>> Saxonica
>>
>>
>>> On 1 May 2017, at 14:00, Costello, Roger L. costello@xxxxxxxxx <xsl-list-service@xxxxxxxxxxxxxxxxxxxxxx> wrote:
>>>
>>> Hi Folks,
>>>
>>> I want an XPath expression that implements this rule:
>>>
>>>       All <A> elements shall be contiguous within <Test>.
>>>
>>> In this example all A's are contiguous, so the rule is satisfied:
>>>
>>> <Test>
>>>    <B/>
>>>    <A/>
>>>    <A/>
>>>    <A/>
>>>    <B/>
>>> </Test>
>>>
>>> In this example there is an intervening B, so the rule is not satisfied:
>>>
>>> <Test>
>>>    <B/>
>>>    <A/>
>>>    <A/>
>>>    <B/>
>>>    <A/>
>>>    <B/>
>>> </Test>
>>>
>>> Below is the XPath that I created. I have two questions about it:
>>>
>>> (1) Is it correct? Do you see anything it would fail to catch?
>>>
>>> (2) Is there a better (simpler, more efficient) XPath expression?
>>>
>>> Here is the XPath (within a Schematron rule):
>>>
>>> <sch:rule context="Test">
>>>    <sch:assert test="
>>>        every $i in A satisfies
>>>           (if ($i/preceding-sibling::A) then $i/preceding-sibling::*[1][self::A] else true())
>>>           and
>>>           (if ($i/following-sibling::A) then $i/following-sibling::*[1][self::A] else true())
>>>        ">
>>>        All A's shall be contiguous within Test.
>>>    </sch:assert>
>>> </sch:rule>
>>>
>> 
>
>
>
> --
> Cheers,
> Dimitre Novatchev
> ---------------------------------------
> Truly great madness cannot be achieved without significant intelligence.
> ---------------------------------------
> To invent, you need a good imagination and a pile of junk
> -------------------------------------
> Never fight an inanimate object
> -------------------------------------
> To avoid situations in which you might make mistakes may be the
> biggest mistake of all
> ------------------------------------
> Quality means doing it right when no one is looking.
> -------------------------------------
> You've achieved success in your field when you don't know whether what
> you're doing is work or play
> -------------------------------------
> To achieve the impossible dream, try going to sleep.
> -------------------------------------
> Facts do not cease to exist because they are ignored.
> -------------------------------------
> Typing monkeys will write all Shakespeare's works in 200yrs.Will they
> write all patents, too? :)
> -------------------------------------
> Sanity is madness put to good use.
> -------------------------------------
> I finally figured out the only reason to be alive is to enjoy it.



-- 
Cheers,
Dimitre Novatchev
---------------------------------------
Truly great madness cannot be achieved without significant intelligence.
---------------------------------------
To invent, you need a good imagination and a pile of junk
-------------------------------------
Never fight an inanimate object
-------------------------------------
To avoid situations in which you might make mistakes may be the
biggest mistake of all
------------------------------------
Quality means doing it right when no one is looking.
-------------------------------------
You've achieved success in your field when you don't know whether what
you're doing is work or play
-------------------------------------
To achieve the impossible dream, try going to sleep.
-------------------------------------
Facts do not cease to exist because they are ignored.
-------------------------------------
Typing monkeys will write all Shakespeare's works in 200yrs.Will they
write all patents, too? :)
-------------------------------------
Sanity is madness put to good use.
-------------------------------------
I finally figured out the only reason to be alive is to enjoy it.