Construct an IDREF
value from an item value.
The following construct(s) refer to this construct:
xs:IDREF(item $value) => IDREF
This is a constructor function that takes an item value as argument and
returns a value of type xs:IDREF
. If the argument is a literal,
then the literal must be a valid lexical form of its type.
As specified in the respective section of the W3C recommendation
XML
Schema Part 2: Datatypes, a value of type xs:IDREF
denotes an ID attribute type, as defined in the
XML 1.0 recommendation. It is derived from the type
xs:NCName
and the lexical form of xs:IDREF
is the set
of all strings that match the production of
NCName.
For compatibility reasons values of this type should only be used as attribute values.
$value |
item value |
---|
The following queries generate valid values of type
xs:IDREF
xs:IDREF("_header")
xs:IDREF("R2D2")
The following queries generate invalid values of type
xs:IDREF
xs:IDREF("-header")
xs:IDREF("1A")