Use of ID attribute types.

["Rodriguez, Sergio" <srodriguez@canella.com.gt>]

Greetings, XML gurus. {:o)

  I have a few questions around the use of ID attributes:

1) As far as I know the ID attributes have a scope of uniqueness within a
document instance, that is, these are unique in the whole document.  Is
there a mechanism, probably an extension of XML, where I can define the
scope of ID attributes whitin a document fragment using a scheme language?
(I know that this I can't achieve it using a DTD, right?)  e.g. the
following example would be valid...

<root>
  <element-one   id-attribute="ALUX" />  <!-- use the same ID -->
  <element-two   id-attribute="TIKAL" />
  <element-three id-attribute="ALUX" />  <!-- use the same ID -->
</root>

2) The use of XML namespace in ID attributes:  if I define two namespaces
within a document, and those namespace include some attributes where their
names are the same and they are ID attributes too... then I could have the
same ID values which would be semantically different, right? and thus, they
would be different ID values (I hope I have expressed it right). Example:

<root xmlns:a="some-URI" xmlns:b="another-URI">
  <element-one   a:id-attribute="ALUX" />
  <element-two   a:id-attribute="TIKAL" />
  <element-three b:id-attribute="ALUX" /> <!-- this would be a different ID
value, because it belongs to another namespace.  Is this correct? -->
</root>

  Pardon me english.  {:o)

Thanks for the help.

Cheers,

Sergio Rodríguez.
CANELLA, S. A.
C. A. / GT