<valList>

<valList> (value list) contains one or more valItem elements defining possible values for an attribute. 22.4.5 Attribute List Specification
Module tagdocs — 22 Documentation Elements
In addition to global attributes att.combinable (@mode)
type specifies the extensibility of the list of attribute values specified.
Status Optional
Legal values are:
closed
only the values specified are permitted.
semi
(semi-open) all the values specified should be supported, but other values are legal and software should have appropriate fallback processing for them.
open
the values specified are sample values only. [Default]
Used by
attDef elementSpec
May contain
tagdocs: valItem
Declaration 

<rng:element name="valList">
 <rng:ref name="att.global.attributes"/>
 <rng:ref name="att.combinable.attributes"/>
 <rng:optional>
  <rng:attribute name="type" a:defaultValue="open">
   <rng:choice>
    <rng:value>closed</rng:value>
    <rng:value>semi</rng:value>
    <rng:value>open</rng:value>
   </rng:choice>
  </rng:attribute>
 </rng:optional>
 <rng:zeroOrMore>
  <rng:ref name="valItem"/>
 </rng:zeroOrMore>
</rng:element>
element valList
{
   att.global.attributes,
   att.combinable.attributes,
   attribute type { "closed" | "semi" | "open" }?,
   valItem*
}
Example
<valList type="closed">
 <valItem ident="req">
  <gloss>required</gloss>
 </valItem>
 <valItem ident="mwa">
  <gloss>mandatory when applicable</gloss>
 </valItem>
 <valItem ident="rec">
  <gloss>recommended</gloss>
 </valItem>
 <valItem ident="rwa">
  <gloss>recommended when applicable</gloss>
 </valItem>
 <valItem ident="opt">
  <gloss>optional</gloss>
 </valItem>
</valList>