<attDef>  (attribute definition) contains the definition of a single attribute. [22.4.5  Attribute List SpecificationModule tagdocs — 22  Documentation Elements Attributes att.global  (@xml:id , @n , @xml:lang , @rend , @rendition , @xml:base , @xml:space )  (att.global.linking  (@corresp , @synch , @sameAs , @copyOf , @next , @prev , @exclude , @select ))  (att.global.analytic  (@ana ))  (att.global.facs  (@facs ))  (att.global.change  (@change )) att.identified  (@ident , @predeclare , @module , @status )  (att.combinable  (@mode )) 
    usage specifies the optionality of the attribute.Status  Optional Legal values are: req (required)  mwa (mandatory when applicable )  rec (recommended )  rwa (recommended when applicable )  opt (optional )  [Default]  
 ns (namespace) specifies the namespace to which this attribute belongs 
Used by 
Contained by May contain Declaration Compact to XML format XML format to compact <rng:element name="attDef "> <rng:ref name="att.global.attributes  <rng:ref name="att.global.linking.attributes  <rng:ref name="att.global.analytic.attributes  <rng:ref name="att.global.facs.attributes  <rng:ref name="att.global.change.attributes  <rng:ref name="att.identified.attributes  <rng:ref name="att.combinable.attributes  <rng:optional> <rng:attribute name="usage " a:defaultValue="opt "> <rng:choice> <rng:value> req</rng:value> <rng:value> mwa</rng:value> <rng:value> rec</rng:value> <rng:value> rwa</rng:value> <rng:value> opt</rng:value> </rng:choice> </rng:attribute> </rng:optional> <rng:optional> <rng:attribute name="ns "http://www.tei-c.org/ns/1.0 "> <rng:ref name="data.namespace  </rng:attribute> </rng:optional> <rng:group> <rng:zeroOrMore> <rng:ref name="model.glossLike  </rng:zeroOrMore> <rng:optional> <rng:ref name="datatype  </rng:optional> <rng:zeroOrMore> <rng:ref name="constraintSpec  </rng:zeroOrMore> <rng:optional> <rng:ref name="defaultVal  </rng:optional> <rng:optional> <rng:choice> <rng:ref name="valList  <rng:oneOrMore> <rng:ref name="valDesc  </rng:oneOrMore> </rng:choice> </rng:optional> <rng:zeroOrMore> <rng:ref name="exemplum  </rng:zeroOrMore> <rng:zeroOrMore> <rng:ref name="remarks  </rng:zeroOrMore> </rng:group> </rng:element> 
element  attDef 
{
   att.global.attributes ,
   att.global.linking.attributes ,
   att.global.analytic.attributes ,
   att.global.facs.attributes ,
   att.global.change.attributes ,
   att.identified.attributes ,
   att.combinable.attributes ,
   attribute usage { "req" | "mwa" | "rec" | "rwa" | "opt" }?,
   attribute ns { data.namespace  }?,
   (
      model.glossLike *,
      datatype ?,
      constraintSpec *,
      defaultVal ?,
      ( valList  | valDesc + )?,
      exemplum *,
      remarks *
   )
} Example 
    <attDef usage="rec " ident="type ">  <desc> specifies a name conventionally used for this level of subdivision, e.g. 
<val> act
</val> , 
<val> volume
</val> , 
<val> book
</val> , 
<val> section
</val> , 
<val> canto
</val> ,
   etc.
</desc> </attDef>