The Not Condition
The Not Condition can be used to negate an other condition.
Example:
<condition type="..." id="standardinstallation">...</condition>
<condition type="not" id="custominstallation">
<condition type="ref" refid="standardinstallation" />
</condition>
Nested Elements
The Not condition must have one and only one reference to an other condition.
condition
A reference to a condition, which will be negated.