--- a/model/ProvenanceModel.html Tue Nov 15 17:56:34 2011 -0500
+++ b/model/ProvenanceModel.html Wed Nov 16 14:32:56 2011 +0000
@@ -1069,12 +1069,24 @@
<p>In PROV-DM, a <dfn id="dfn-Use">use record</dfn> is a representation of a world event: the consumption of an entity by an activity. The representation includes a description of the modalities of use of this entity by this activity.</p>
+
+<p>A use record, written <span class="name">used(id,a,e,attrs,t)</span> in PROV-ASN, has the following constituent:</p>
+<ul>
+<li><em>id</em>: an OPTIONAL identifier <span class="name">id</span> identifying the use record;</li>
+<li><em>activity</em>: an identifier <span class="name">a</span> for an activity record, which represents the consuming activity;</li>
+<li><em>entity</em>: an identifier <span class="name">e</span> for an entity record, which represents the entity that is consumed;</li>
+<li><em>attributes</em>: a set of attribute-value pairs <span class="name">attrs</span> that describe the modalities of use of this entity by this activity;</li>
+<li><em>time</em>: an OPTIONAL "use time" <span class="name">t</span>, the time at which the entity was used.</li>
+</ul>
+
<p>In PROV-ASN, a use record's text matches the <span class='nonterminal'>useRecord</span> production of the grammar defined in this specification document.</p>
<div class='grammar'>
<span class="nonterminal">useRecord</span> :=
<span class="name">used</span>
<span class="name">(</span>
+[<span class="nonterminal">identifier</span>
+<span class="name">,</span>]
<span class="nonterminal">identifier</span>
<span class="name">,</span>
<span class="nonterminal">identifier</span>
@@ -1083,17 +1095,9 @@
[<span class="name">,</span>
<span class="nonterminal">time</span>]
<span class="name">)</span><br/>
-<br/>
</div>
-<p>A use record, written <span class="name">used(pe,e,attrs,t)</span> in PROV-ASN:</p>
-<ul>
-<li> refers to an activity record identified by <span class="name">pe</span>, which represents the consuming activity;</li>
-<li> refers to an entity record identified by <span class="name">e</span>, which represents the entity that is consumed;</li>
-<li> contains a set of attribute-value pairs <span class="name">attrs</span> that describe the modalities of use of this entity by this activity;</li>
-<li> MAY contain a "use time" <span class="name">t</span>, the time at which the entity was used.</li>
-</ul>
<p>The following use assertions</p>
@@ -1104,6 +1108,11 @@
<p>state that the activity, represented by the activity record identified by <span class="name">pe1</span>, consumed two entities, represented by entity records identified by <span class="name">e1</span> and <span class="name">e2</span>, at times <span class="name">t1</span> and <span class="name">t2</span>, respectively; the first one was found as the value of parameter <span class="name">p1</span>, whereas the second was found as value of parameter <span class="name">p2</span>. The semantics of <span class="name">parameter</span> in these records is application specific.</p>
+<p>
+A use record's id is OPTIONAL, but comes handy when annotating use records (see Section <a href="#record-annotationAssociation">Annotation Association Record</a>) or when defining derivations (see <a href="#pe-linked-derivationRecord"><span class='nonterminal'>pe-linked-derivationRecord</span></a>).
+</p>
+
+
<p>A reference to a given entity record MAY appear in multiple use records that share
a given activity record identifier. If one wants to annotate a use record or if one wants to express a <a href="#pe-linked-derivationRecord"><span class='nonterminal'>pe-linked-derivationRecord</span></a> referring to this entity and activity records, the attributes occuring in this use assertion MUST be unique among the attributes of other use records for this activity
</p>