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| 54 | <H2><A NAME="SECTION0014140000000000000000"></A><A NAME="writer-impls"></A> |
| 55 | <BR> |
| 56 | 12.1.4 Writer Implementations |
| 57 | </H2> |
| 58 | |
| 59 | <P> |
| 60 | Three implementations of the writer object interface are provided as |
| 61 | examples by this module. Most applications will need to derive new |
| 62 | writer classes from the <tt class="class">NullWriter</tt> class. |
| 63 | |
| 64 | <P> |
| 65 | <dl><dt><table cellpadding="0" cellspacing="0"><tr valign="baseline"> |
| 66 | <td><nobr><b><span class="typelabel">class</span> <tt id='l2h-3824' xml:id='l2h-3824' class="class">NullWriter</tt></b>(</nobr></td> |
| 67 | <td><var></var>)</td></tr></table></dt> |
| 68 | <dd> |
| 69 | A writer which only provides the interface definition; no actions are |
| 70 | taken on any methods. This should be the base class for all writers |
| 71 | which do not need to inherit any implementation methods. |
| 72 | </dl> |
| 73 | |
| 74 | <P> |
| 75 | <dl><dt><table cellpadding="0" cellspacing="0"><tr valign="baseline"> |
| 76 | <td><nobr><b><span class="typelabel">class</span> <tt id='l2h-3825' xml:id='l2h-3825' class="class">AbstractWriter</tt></b>(</nobr></td> |
| 77 | <td><var></var>)</td></tr></table></dt> |
| 78 | <dd> |
| 79 | A writer which can be used in debugging formatters, but not much |
| 80 | else. Each method simply announces itself by printing its name and |
| 81 | arguments on standard output. |
| 82 | </dl> |
| 83 | |
| 84 | <P> |
| 85 | <dl><dt><table cellpadding="0" cellspacing="0"><tr valign="baseline"> |
| 86 | <td><nobr><b><span class="typelabel">class</span> <tt id='l2h-3826' xml:id='l2h-3826' class="class">DumbWriter</tt></b>(</nobr></td> |
| 87 | <td><var></var><big>[</big><var>file</var><big>[</big><var>, maxcol<code> = 72</code></var><big>]</big><var></var><big>]</big><var></var>)</td></tr></table></dt> |
| 88 | <dd> |
| 89 | Simple writer class which writes output on the file object passed in |
| 90 | as <var>file</var> or, if <var>file</var> is omitted, on standard output. The |
| 91 | output is simply word-wrapped to the number of columns specified by |
| 92 | <var>maxcol</var>. This class is suitable for reflowing a sequence of |
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