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Copyright (c) 2000-2021 Ericsson Telecom AB
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Contributors:
Baji, Laszlo
Balasko, Jeno
Csorba, Mate
Forstner, Matyas
Szabados, Kristof
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<title>ispresent</title>
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<h1>ispresent</h1>
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<p>This function returns the value <b><font face="Courier New">true</font></b> if and only if the value of the referenced field is present in the actual instance of the referenced data object.
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<p>Related keyword:</p>
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<li><b><font face="Courier New" size="4" color="#003258"> <a href="boolean.html">boolean</a></font></b></li>
<li><b><a href="true.html"><font face="Courier New" size="4" color="#003258"> true</font></a></b></li>
<li><b><font face="Courier New" size="4" color="#003258"><a href="false.html"> false</a></font></b></li>
<li><b><font face="Courier New" size="4" color="#003258"> <a href="optional.html">optional</a></font></b></li>
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<h3 align="center"><font face="Courier New" color="#003258" size="5"><b>ispresent</b></font> <font face="Courier New" color="#003258" size="5"><b> (</b></font><i>any_type value</i><font
face="Courier New" color="#003258" size="5"><b>)return boolean</b></font></h3>
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<ul>
<li>
<p><i>any_type value</i> shall be a reference to a field within a data object that is defined as being <b><font face="Courier New">optional</font></b>.</p>
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</ul>
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<p>Example 1:</p>
<p><font face="Courier New">type record MyRecordType { <br>
boolean field1 optional,<br>
integer field2<br>
}<br>
...</font></p>
<p><font face="Courier New">var MyRecordType v_MyRecordType;<br>
...</font></p>
<p><font face="Courier New">MyPort.receive(MyRecordType: ?) -> value v_MyRecordType<br>
{<br>
if (ispresent(v_MyRecordType.field1))<br>
{...}<br>
...</font></p>
<p>The record <font face="Courier New">MyRecordType</font> with an optional field has been received and stored in a variable. Then the presence of <font face="Courier New">field1</font> is
checked. Decisions can be made on the result of the <b><font face="Courier New">ispresent</font></b> function.</p>
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