Re: In a type dependency chain, what is the highest type in the chain called?

On 26/04/2011 18:24, Costello, Roger L. wrote:
> Hi Folks,
>
> In the below type dependency chain BostonAreaSurfaceElevation restricts EarthSurfaceElevation which restricts Elevation which restricts xsd:integer.
>
> So, xsd:integer is at the top of the chain.
No it isn't. xs:integer is derived from xs:decimal, which is derived 
from xs:anyAtomicType, which is derived from xs:anySimpleType, which is 
derived from xs:anyType.

The head of the chain is called xs:anyType. XSD 1.0 also called it the 
ur-type, because that sounded clever.

The types that are derived directly from xs:anyAtomicType (in this case 
xs:decimal) are called primitive types.

Michael Kay
Saxonica

> What is that called? The start type? The head type? The beginning type? The primal type? If there is no official name, what name do you like?
>
> /Roger
>
>      <xsd:simpleType name="Elevation">
>          <xsd:restriction base="xsd:integer">
>              <xsd:minInclusive value="-999999"/>
>              <xsd:maxInclusive value="999999"/>
>          </xsd:restriction>
>      </xsd:simpleType>
>
>      <xsd:simpleType name="EarthSurfaceElevation">
>          <xsd:restriction base="elev:Elevation">
>              <xsd:minInclusive value="-1290"/>
>              <xsd:maxInclusive value="29035"/>
>          </xsd:restriction>
>      </xsd:simpleType>
>
>      <xsd:simpleType name="BostonAreaSurfaceElevation">
>          <xsd:restriction base="elev:EarthSurfaceElevation">
>              <xsd:minInclusive value="0"/>
>              <xsd:maxInclusive value="120"/>
>          </xsd:restriction>
>      </xsd:simpleType>
>
>
>
>