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this is an interesting idea?
On Mon, 17 Jul 2006, Philippe Poulard wrote:
> hi,
>
> namespace URIs are used to disambiguish names used in elements (and
> sometimes in attributes) ; the idea is to consider that a name has 2
> parts, an ID and a local name ; 2 elements that have the same local name
> are distinct when the ID you choose is not the same than mine ; now what
> would happenned if unfortunately we have both choosen the same ID ? we
> would have a clash ; the solution would be :
> 1) to disambiguish again our elements by considering that a name has 3
> parts (an ID, another ID and a local name) ; now loop again if we choose
> again the same IDs
> 2) to choose a better ID
>
> so we must ensure that when you choose an ID, it is not the same than
> mine ; the idea is to use a "universal ID", an ID that is unique all
> over the world
>
> candidates :
> -URIs ("http://foo.com/myNs"; or "urn:isbn:9-780201-770049")
> -GUIDs (they are also expressible with URN : "urn:guid:etc...")
> -à la Java ("com.foo.myNs")
> -...
>
> URIs win
>
> avoid using "that text document" : even if XML processors won't complain
> because it's not an URI string, it is not a unique string
>
> so, the kind of URI you could use could be something like this :
> "http://lle.rochester.edu/myProject/myNs";
> or
> "tag:dgresh@lle.rochester.edu:2006-07-17:myNs"
> or any other, as long as it is unique
>
> Daniel Gresh wrote:
> > I have a basic question about XML Namespaces, as I just cannot seem to
> > fully grasp the concept.
> >
> > I know how to set up a namespace, and I know how they are used in the
> > document and such; my question is mainly about the URI associated with a
> > namespace. Let's use this as an example:
> >
> > |<x xmlns:edi='http://ecommerce.org/schema'>
> > <!-- the 'price' element's namespace is http://ecommerce.org/schema -->
> > <edi:price units='Euro'>32.18</edi:price>
> > </x>||
> >
> > Now I'm not too sure how to phrase this question, but here goes: do I
> > have to associate a URI with a namespace? In the above example, what
> > would be the case if there was no xmlns declaration and the ns "edi" was
> > used? I suppose what I am asking is: what is the benefit of declaring an
> > xmlns in the manner xmlns:prefix='URI'? Is information from that URI
> > being used in the XML document somehow? It's all very confusing to me.
> >
> > Also, let's say I have a simple text document located somewhere on my
> > hard drive, like C:\document.txt. If I wanted to define a namespace for
> > that document, such as xmlns:doc='that text document', how exactly
> > would I do so? Is it even needed?
> >
> > Thanks in advance,
> > Dan
> > |
> >
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