• From: Michael Kay <mike@s...>
• To: "Costello, Roger L." <costello@m...>, "xml-dev@l... >> \"xml-dev@l...\"" <xml-dev@l...>
• Date: Sat, 19 Mar 2011 23:41:37 +0000

> Consider this XML snippet:
>
>    <altitude units="feet">12000</altitude>
>
> I have heard it stated:
>
>     The units attribute provides data about the
>     element's data. That is, units provides
>     metadata.
>
> However, the XML specification makes no such claim about attributes providing "metadata". This is what the XML specification says:
>
>    Attributes are used to associate name-value pairs with elements.
>
> And then the specification goes on to describe the specific syntax for attributes.
>
> Thus, attributes don't provide data about an element's content. Attributes don't provide metadata.

That's a bit like arguing "The XML specification doesn't say that 12000 
is an integer. Therefore 12000 is not an integer."

Michael Kay
Saxonica

• References:
  • Abandon the (mistaken) belief that XML attributes provide"metadata" and set yourself free to explore capability-based designs
    • From: "Costello, Roger L." <costello@m...>