help/info/null.html

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   9   Baji, Laszlo
  10   Balasko, Jeno
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  18 <title>null</title>
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  36 <hr>
  37 <h1>null</h1>
  38 <hr align="left" width="75%">
  39 <p>This special value refers to something undefined. It may indicate...</p>
  40 <ul>
  41   <li>an undefined <a href="altstep.html"><b><font face="Courier New" size="4">default</font></b></a> reference, e.g. for the initialization of variables to handle default references (i.e., <a
  42     href="altstep.html"><b><font face="Courier New" size="4">activate</font></b></a>d <a href="altstep.html"><b><font face="Courier New" size="4">altstep</font></b></a>s).</li>
  43   <li>an undefined <a href="address.html"><b><font face="Courier New" size="4">address</font></b></a>, e.g. for the initialization of variables of the address type.</li>
  44 </ul>
  45 <p>Related keywords:</p>
  46 <ul>
  47   <li><a href="address.html"><b><font face="Courier New" color="#003258" size="4">address</font></b></a></li>
  48   <li><a href="altstep.html"><b><font face="Courier New" color="#003258" size="4">altstep</font></b></a></li>
  49   <li><a href="activate.html"><b><font face="Courier New" color="#003258" size="4">activate</font></b></a></li>
  50   <li><a href="default.html"><b><font face="Courier New" color="#003258" size="4">default</font></b></a></li>
  51 </ul>
  52 <hr align="left" width="50%">
  53 <div align="center">
  54 <center>
  55 <table border="0" width="90%" bgcolor="#FFB599" cellpadding="4">
  56   <tr>
  57     <td width="100%">
  58     <h3 align="center"><font face="Courier New" color="#003258" size="5"><b>null</b></font></h3>
  59     </td>
  60   </tr>
  61 </table>
  62 </center>
  63 </div>
  64 <hr align="left" width="50%">
  65 <p>Example 1:
  66 <p><font face="Courier New">var default vd_DefaultVariable := null; </font>
  67 <p>The variable vd_DefaultVariable is declared and given the initial value null.</p>
  68 <hr align="left" width="50%">
  69 <p>Example 2:
  70 <p><font face="Courier New">var address v_MySUTentity := null; </font>
  71 <p>The variable v_MySUTentity is declared and given the initial value null.</p>
  72 <hr align="left" width="25%">
  73 <hr align="left" width="25%">
  74 <p><a HREF="BNF.html#activateop">BNF definition</a> of <font face="Courier New">null</font></p>
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