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Most applications will need to derive new writer classes from the <tt class="class">NullWriter</tt> class. <P> <dl><dt><table cellpadding="0" cellspacing="0"><tr valign="baseline"> <td><nobr><b><span class="typelabel">class</span> <tt id='l2h-3535' class="class">NullWriter</tt></b>(</nobr></td> <td>)</td></tr></table></dt> <dd> A writer which only provides the interface definition; no actions are taken on any methods. This should be the base class for all writers which do not need to inherit any implementation methods. </dl> <P> <dl><dt><table cellpadding="0" cellspacing="0"><tr valign="baseline"> <td><nobr><b><span class="typelabel">class</span> <tt id='l2h-3536' class="class">AbstractWriter</tt></b>(</nobr></td> <td>)</td></tr></table></dt> <dd> A writer which can be used in debugging formatters, but not much else. Each method simply announces itself by printing its name and arguments on standard output. </dl> <P> <dl><dt><table cellpadding="0" cellspacing="0"><tr valign="baseline"> <td><nobr><b><span class="typelabel">class</span> <tt id='l2h-3537' class="class">DumbWriter</tt></b>(</nobr></td> <td><big>[</big><var>file</var><big>[</big><var>, maxcol<code> = 72</code></var><big>]</big><big>]</big>)</td></tr></table></dt> <dd> Simple writer class which writes output on the file object passed in as <var>file</var> or, if <var>file</var> is omitted, on standard output. The output is simply word-wrapped to the number of columns specified by <var>maxcol</var>. 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