Overview#A substring assertion is the argument provided to a substring matchingRule in the process of determining whether an attribute has any Attribute Value that matches a given substring.
The substring assertion contains at least one component from the following set:
- Zero or one subInitial element, which must appear at the beginning of the target value.
- Zero or more subAny elements, which may appear anywhere in the middle of the value. If there are multiple subAny elements, then a matching attribute value must contain all of the subAny elements in the order they appear in the substring assertion with no overlap (i.e., no character in an attribute value can be part of two different substring assertion components). If subInitial and/or subFinal components are present, then none of the subAny elements may overlap with them either.
- Zero or one subFinal element, which must appear at the end of the target value.
The substring assertion is used when processing a Substring Search Filter.