word">void</span> <a name="idp59917472-bb"></a><span class="identifier">add_format</span><span class="special">(</span><span class="identifier">output_format</span><span class="special">)</span><span class="special">;</span></pre>Add a format to the set of loggers. <p>Adding a logger means that the specified logger is enabled. The log level is managed by the formatter itself and specifies what events are forwarded to the underlying formatter. </p>
<p><b>Since Boost 1.62 .&#160;</b></p>
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