xs:restriction(simple content) — Derivation of a simple content model by restriction.
<xs:restriction
base = xs:QName
id = xs:ID
{any attributes with non-schema namespace}
>
Content: (xs:annotation?, (xs:simpleType?, (xs:minExclusive |
xs:minInclusive | xs:maxExclusive | xs:maxInclusive |
xs:totalDigits | xs:fractionDigits | xs:length |
xs:minLength | xs:maxLength | xs:enumeration | xs:whiteSpace |
xs:pattern)*)?, ((xs:attribute | xs:attributeGroup)*,
xs:anyAttribute?))
</xs:restriction>
May be included in: xs:simpleContent
The restriction of simple content complex types is an operation that allows the addition of new constraints to both the attributes and the text node allowed in simple content elements (this reduces the set of valid instances structures). The restriction of the text node is done using the same facets that are available for restricting simple types; the restriction of the attributes is done by providing a list of modified attribute definitions or references. The attribute types used in this list must be identical or explicit derivations by restriction of the types used during the definition of the base type. The controls applied to the attributes must result in a restriction of their definition (for instance, a value may be fixed, an attribute that was optional may become either required or prohibited, etc.).
The same element name (xs:restriction) is used in
three different contexts with highly different meanings. Be careful
to distinguish restriction in the context of a simple datatype, a
simple content model, and a complex content model.
<xs:element name="title">
<xs:complexType>
<xs:simpleContent>
<xs:restriction base="tokenWithLangAndNote">
<xs:maxLength value="255"/>
<xs:attribute name="lang">
<xs:simpleType>
<xs:restriction base="xs:language">
<xs:enumeration value="en"/>
<xs:enumeration value="es"/>
</xs:restriction>
</xs:simpleType>
</xs:attribute>
</xs:restriction>
</xs:simpleContent>
</xs:complexType>
</xs:element>