RE: Word of the day: upconversion

["Costello, Roger L." <costello@mitre.org>]

Hi Folks,

Great comments!  Thank you!

Here's a follow on question ...

Below are two ways of expressing the constraint on a <Color> element. The first uses XML to express the constraint and the second uses XPath.


1. XML

    <element name="Color">
        <simpleType>
            <restriction base="string">
                <enumeration value="red" />
                <enumeration value="green" />
                <enumeration value="blue" />
            </restriction>
        </simpleType>
    </element>


2. XPath

    <element name="Color">
        <complexType>
            <simpleContent>
                <extension base="string">
                    <assert test="(. eq 'red') or (. eq 'green') or (. eq 'blue')" />
                </extension>
            </simpleContent>
        </complexType>
    </element>


Note: the second uses the new assertion capability in XML Schema 1.1. It uses XPath to express constraints.


If you're doing upconversion, would you upconvert this XML:

    <enumeration value="red" />
    <enumeration value="green" />
    <enumeration value="blue" />

to this XPath:

    (. eq 'red') or (. eq 'green') or (. eq 'blue')

or vice versa?

Is the XML richer in structure and information or is the XPath?

/Roger