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Hi Syd and all,

One more little thing, about the xsd:anyURI check: I can't get it to 
work, and the problem appears to only concern xsd:anyURI, whether I use 
(1) to go via the TEI layer or (2) directly.

(1) <dataRef key="teidata.pointer"/>

(2) <dataRef name="anyURI"/>

If I do, e.g.

<sch:assert test="@my_attribute castable as xsd:anyURI">,

I can put anything into the attribute value, and it won't get flagged by 
Schematron. I have done these checks with other data types, directly or 
indirectly, and they all worked (so it's not that I use wrong syntax or 
anything of that sort), but the behaviour of anyURI is different.

Is there some insider info anyone would care to share on this, please?

I looked for other examples of that within TEI/P5 and in Stylesheets, 
but wasn't able to find any.

While composing this message, I found the following passage in the W3C 
spec on XSD datatypes, and I hope I interpret it wrongly when I think 
that this may be the issue:

"Because it is impractical for processors to check that a value is a 
context-appropriate URI reference, this specification follows the lead 
of [RFC 2396] (as amended by [RFC 2732]) in this matter: such rules and 
restrictions are not part of type validity and are not checked by 
·minimally conforming· processors. Thus in practice the above definition 
imposes only very modest obligations on ·minimally conforming· processors."

https://www.w3.org/TR/xmlschema-2/#anyURI

Would be correct to assume that we're looking at a "minimally 
conforming" behaviour here? My checks were tested in oXygen, but also 
during the TEI/P5 build process, which also validates with Schematron.

And a practical question: should I rather validate against a regex than 
use `castable as xsd:anyURI`?

Thanks in advance!

   Piotr

On 23/03/17 18:42, Syd Bauman wrote:
> I tihnk the short answer is "no", Pure ODD can't do that. But to be
> honest, I haven't tried. This is in part because I know the `roma`
> code that handles <attList org="choice"> is broken. (See bug 144.[1])
>
> But ODD can do this, albeit in a roundabout, hack kind of way. (And,
> it turns out in writing my test, I had to add a hack to the hack to
> get around what I presume is a bug in ODD processing.)
>
> The attached ODD is an example of a method that at best is likely to
> be considered controversial, at worst bad practice. But it does
> exactly what (I think) you want. It re-names the element <hi> to be
> <methodOne>, and gives it three new required
> attributes:
>   attribute.1 = "pointer" | "character" | "byte_offset" | "time_in_sec"
>   attribute.2 =  anyURI       nonNegInt     nonNegInt       int
>   attribute.3 =  anyURI       nonNegInt     nonNegInt       int
>
> A few caveats, in no particular order:
>
>  * The method used will give some people angina.
>
>  * Because RELAX NG cosntructs are used directly, you do not have the
>    advantage that the value of attribute.3 is defined as
>    teidata.pointer when attribute.1 is "pointer"; rather, it is
>    defined directly as anyURI.
>
>  * Hack: I had to use <rng:interleave> to group the attribute
>    definitions; for some reason when I tried <rng:group> (which is
>    what one would naturally expect to use) `roma` converted it to an
>    <rng:choice>.
>
>  * I really doubt you can get usable XSD, and you certainly can get
>    helpful DTD, out of this.
>
> So personally, I prefer the solution you recommended: just create a
> closed list for @attribute.1, and then a small Schematron rule to
> ensure that @attribute.2 and @attribute.3 are of the right datatype.
>
> I have thrown that into the ODD as well, renaming <emph> to be
> <methodTwo>, and giving it three new required attributes named
> "anotherAtt.1" etc.
>
> Notes
> -----
> [1] https://github.com/TEIC/Stylesheets/issues/144
>
>
>
>
>> I would like to define an alternation of patterns of up to three
>> attributes, where the datatype of attribute.2 and attribute.3 is uniform
>> and depends on the value of attribute.1.
>>
>> Something like the following (in **pseudo-markup**):
>>
>> <rng:choice>
>>     <rng:group>  "pointer", data.pointer,
>> data.pointer </rng:group>
>>     <rng:group>  "character",   data.nonNegativeInteger,
>> data.nonNegativeInteger </rng:group>
>>     <rng:group>  "byte_offset", data.nonNegativeInteger,
>> data.nonNegativeInteger </rng:group>
>>     <rng:group>  "time_in_sec", data.integer,
>> data.integer </rng:group>
>>    .... etc.
>> </rng:choice>
>>
>> I could do that in RNG, but can I do that in ODD as well?
>>
>> If I understand correctly, ODD expects me to list the three attDef
>> declarations in an <attList> for my new class, and to declare a new data
>> type that groups the data types that I need for attribute.2 and
>> attribute.3, and to make the value of attribute.1 a closed list, and
>> then to slam a huuuge piece of Schematron onto this (hopefully inside
>> this very class definition; I haven't checked that) that would attempt
>> to rule out unwanted sequences.
>>
>> Is my diagnosis correct? I probably wouldn't mind being wrong.
>>
>> I also admit to having a rather hazy idea of the extent of the
>> difference in "staticness" between listing potential patterns in an RNG
>> schema on the one hand, and defining them in the ODD on the other. I
>> mean, I am not really sure if I could <alternate> a series of
>> <sequence>s containing <attDef>s. Would I end up defining a single
>> attribute several times? Would/Should ODD allow me to do that?