<alt>

<alt> (alternation) identifies an alternation or a set of choices among elements or passages. 16.8 Alternation
Modul linking — 16 Linking, Segmentation, and Alignment
Neben global gültigen Attributen att.pointing (@target, @evaluate) att.typed (@type, @subtype)
targets specifies the identifiers of the alternative elements or passages.
Zustand Optional
Datentyp 2–∞ Vorkommen von  

<rng:ref name="data.pointer"/>
data.pointer
Durch Leerzeichen getrennt
Werte Each value specified must be the same as that specified as value for an xml:id attribute for some other element in the current document.
mode states whether the alternations gathered in this collection are exclusive or inclusive.
Zustand Empfohlen
Gültige Werte:
excl
(exclusive) indicates that the alternation is exclusive, i.e. that at most one of the alternatives occurs.
incl
(inclusive) indicates that the alternation is not exclusive, i.e. that one or more of the alternatives occur.
weights If mode is excl, each weight states the probability that the corresponding alternative occurs. If mode is incl each weight states the probability that the corresponding alternative occurs given that at least one of the other alternatives occurs.
Zustand Optional
Datentyp 2–∞ Vorkommen von  

<rng:ref name="data.probability"/>
data.probability
Durch Leerzeichen getrennt
Werte a whitespace-separated list of probability values in the range from 0 to 1.
Verwendet von
altGrp model.global.meta
Kann enthalten Leeres Element
Deklaration 

<rng:element name="alt">
 <rng:ref name="att.global.attributes"/>
 <rng:ref name="att.pointing.attributes"/>
 <rng:ref name="att.typed.attributes"/>
 <rng:optional>
  <rng:attribute name="targets">
   <rng:list>
    <rng:ref name="data.pointer"/>
    <rng:ref name="data.pointer"/>
    <rng:zeroOrMore>
     <rng:ref name="data.pointer"/>
    </rng:zeroOrMore>
   </rng:list>
  </rng:attribute>
 </rng:optional>
 <rng:optional>
  <rng:attribute name="mode">
   <rng:choice>
    <rng:value>excl</rng:value>
    <rng:value>incl</rng:value>
   </rng:choice>
  </rng:attribute>
 </rng:optional>
 <rng:optional>
  <rng:attribute name="weights">
   <rng:list>
    <rng:ref name="data.probability"/>
    <rng:ref name="data.probability"/>
    <rng:zeroOrMore>
     <rng:ref name="data.probability"/>
    </rng:zeroOrMore>
   </rng:list>
  </rng:attribute>
 </rng:optional>
 <rng:empty/>
</rng:element>
element alt
{
   att.global.attributes,
   att.pointing.attributes,
   att.typed.attributes,
   attribute targets { list { data.pointer, data.pointer, data.pointer* } }?,
   attribute mode { "excl" | "incl" }?,
   attribute weights
   {
      list { data.probability, data.probability, data.probability* }
   }?,
   empty
}
Schematron

<s:report test="@target and @targets">You may not supply both
@target and @targets</s:report>
Schematron

<s:report test="not(@target) and not(@targets)">You must
supply either @target or @targets</s:report>
Schematron

<s:assert test="contains(@target,' ')">You must supply at least two
values for @target</s:assert>
Beispiel
<alt mode="excl" targets="#we.fun #we.sun" weights="0.5 0.5"/>