<when>

<when> indicates a point in time either relative to other elements in the same timeline tag, or absolutely. 16.5.2 Placing Synchronous Events in Time
모듈linking — 16 Linking, Segmentation, and Alignment
속성att.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))
absolutesupplies an absolute value for the time.
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<rng:ref name="data.temporal.w3c"/>
data.temporal.w3c
unitspecifies the unit of time in which the interval value is expressed, if this is not inherited from the parent timeline.
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<rng:ref name="data.enumerated"/>
data.enumerated
제안값은 다음을 포함한다:
d
(days)
h
(hours)
min
(minutes)
s
(seconds)
ms
(milliseconds)
intervalspecifies the numeric portion of a time interval
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<rng:choice>
 <rng:data type="float">
  <rng:param name="minExclusive">0</rng:param>
 </rng:data>
 <rng:value>unknown</rng:value>
</rng:choice>
xsd:float { minExclusive = "0" } | "unknown"
값 a positive number, or the special value unknown.
sinceidentifies the reference point for determining the time of the current when element, which is obtained by adding the interval to the time of the reference point.
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<rng:ref name="data.pointer"/>
data.pointer
값 Should point to another when element in the same timeline.
에 의해 사용된
에 의해 포함된
linking: timeline
포함할 수 있다공백 요소
선언

<rng:element name="when">
 <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:optional>
  <rng:attribute name="absolute">
   <rng:ref name="data.temporal.w3c"/>
  </rng:attribute>
 </rng:optional>
 <rng:optional>
  <rng:attribute name="unit">
   <rng:choice>
    <rng:value>d</rng:value>
    <rng:value>h</rng:value>
    <rng:value>min</rng:value>
    <rng:value>s</rng:value>
    <rng:value>ms</rng:value>
    <rng:data type="Name"/>
   </rng:choice>
  </rng:attribute>
 </rng:optional>
 <rng:optional>
  <rng:attribute name="interval">
   <rng:choice>
    <rng:data type="float">
     <rng:param name="minExclusive">0</rng:param>
    </rng:data>
    <rng:value>unknown</rng:value>
   </rng:choice>
  </rng:attribute>
 </rng:optional>
 <rng:optional>
  <rng:attribute name="since">
   <rng:ref name="data.pointer"/>
  </rng:attribute>
 </rng:optional>
 <rng:empty/>
</rng:element>
element when
{
   att.global.attributes,
   att.global.linking.attributes,
   att.global.analytic.attributes,
   att.global.facs.attributes,
   att.global.change.attributes,
   attribute absolute { data.temporal.w3c }?,
   attribute unit { "d" | "h" | "min" | "s" | "ms" | xsd:Name }?,
   attribute interval { xsd:float { minExclusive = "0" } | "unknown" }?,
   attribute since { data.pointer }?,
   empty
}
예
<when xml:id="TW3" interval="20" since="#w2"/>