ining-the-keywords">
<h3>2.1.3&nbsp;&nbsp;&nbsp;Defining the Keywords</h3>
<p>The point of this exercise is to make it possible to call
<tt class="docutils literal">depth_first_search</tt> with named arguments, leaving out any
arguments for which the default is appropriate:</p>
<pre class="literal-block">
graphs::depth_first_search(g, <strong>color_map_=my_color_map</strong>);
</pre>
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<p>To make that syntax legal, there needs to be an object called
“<tt class="docutils literal">color_map