m>req</em>&nbsp;</td><td>- Whether the argument is required on the command line. </td></tr>
    <tr><td valign="top"></td><td valign="top"><em>value</em>&nbsp;</td><td>- The default value assigned to this argument if it is not present on the command line. </td></tr>
    <tr><td valign="top"></td><td valign="top"><em>constraint</em>&nbsp;</td><td>- A pointer to a <a class="el" href="classTCLAP_1_1Constraint.html" title="The interface that defines the interaction between the Arg and Constraint.">Constraint</a