[tei-council] Examples for certainty|precision @match

[Martin Holmes]

This is a tough one. My instinct is that we should go with what seems to 
be intuitive, and what's most intuitive to me is that if you specify 
nothing, the default is the current context. In other words, the default 
value of @match should be ".", and that if you want to point to a parent 
element, you have to use "..". That means the examples should be 
rewritten to:

<certainty match="../@who" locus="value" degree="0.5"/>

etc. And in realistic usage, the @match attribute would be required, to 
prevent the <certainty> attribute from expressing uncertainty about itself.

This would also make @match in line with @target; if @target contained a 
TEI Pointer of some kind, that would be evaluated relative to the 
current context <certainty>, wouldn't it?

My head hurts when I think about this, though. <certainty> can contain 
<certainty>, meaning that you could have a child <certainty> expressing 
doubt about the value of the parent <certainty>'s @match attribute, 
while the parent <certainty> could express doubt about the child 
<certainty>'s @target. Gawd.

Cheers,
Martin

On 12-11-26 04:41 AM, Gabriel Bodard wrote:
> After fixing the problem with certLike having been inadvertently removed
> from the content model of <space>, I was about to add an example or two
> to the usage of <certainty> and/or <precision>, when I noticed an
> apparent inconsistency (or at least potential confusion) in the
> guidelines description of the @match attribute.
>
> At
> <http://www.tei-c.org/release/doc/tei-p5-doc/en/html/ref-att.scoping.html>,
> @match is defined:
> "supplies an arbitrary XPath expression identifying a set of nodes,
> selected within the context identified by the @target attribute if this
> is supplied, or within the context of the element bearing this attribute
> if it is not."
>
> I take this to mean that in the absence of @target, if I want to point
> to a <gap> element from a <certainty> inside it, I should write:
>
> <gap><certainty match=".."/></gap>
>
> (The example under match indeed gives match="parent::tei:gap/@reason",
> which I take to be consistent with my usage.)
>
> A note further down adds:
> "If neither attribute (sc. @target, @match) is present, the expression
> of certainty applies to the context of the certainty element itself,
> i.e. its parent element." (For starters, this should say "certainty,
> precision etc.".)
>
> But I take this to mean that an element <precision/> should be
> understood to have a default value of match=".." (rather than match="."
> which might be more intuitive). This is not inconsistent, but perhaps
> slightly confusing. (At the very least we should offer more examples here.)
>
> In the examples at
> <http://www.tei-c.org/release/doc/tei-p5-doc/en/html/CE.html#index-body.1_div.21_div.1_div.2_div.4>
> (yuk!) however, we uniformly see values such as:
>
> <certainty match="@who" locus="value" degree="0.5"/>
> <certainty match="@resp" locus="value" degree="0.2"/>
> etc.
>
> Since the certainty element in these cases has neither who nor resp,
> this usage seems to imply that the starting point for the XPath in
> @match is the parent of the [certainty|precision] element that bears the
> @match attribute.
>
> On the one hand, it is probably simplest to say that the examples in CE
> are wrong and we should just fix them by prefixing all of these @ with
> ../ (which is how I've been using this attribute).
>
> On the other, however, if the starting point of the XPath were the
> parent element rather than the [certainty|precision] element itself,
> then it becomes less defensible to have some transcriptional elements
> that cannot take certainty or precision as children, as I argued at the
> last F2F. So I don't mind which way we go on this one. ;-)
>
> Any thoughts?
>
> G
>

-- 
Martin Holmes
mholmes at uvic.ca
UVic Humanities Computing and Media Centre