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<FONT><h3><tt cLASS="monofont">operator</tt></h3>
<p>The <TT CLass="monofont">operator</tT> module stores functions that access the built-in standard operators. The main reason for the <TT Class="monofont">operator</tt> module is that <tt class="monofont">operator.add,</tt> for instance, is much faster than <tt claSs="monofont">lambda a,b: a+b.</tT></p>
<p>For example, the line</p>
<Pre>
>>> import operator
>>> operator.div(6,2)
3
</prE>
<p>provides the same result that the next line does.</p>
<pRE>
>>> 6 / 2
3
</PRe>
<p>This module is mostly used when it becomes necessary to pass an operator as the argument of a function. For example</p>
<pRE>
1: import sys, glob, operator
2: sys.argv = reduce(operator.add, map(glob.glob, sys.argv))
3: print sys.argv
</PRe>
<p>To run the previous example, save the code in a file and execute it by switching to your OS prompt and typing:</p>
<pRE>
python yourfilename.py *.*
</PRe>
<p>The heart of this example is Line 2. Let's interpret it:</p>
<p>The <A NAMe="idx1073742698"></a><a name="idx1073742699"></a><tt class="monofont">glob.glob()</tt> function is applied for each element of the original <tt cLasS="monofont">sys.argv</tt> list object (by using the <a Name="idx1073742700"></a><A namE="idx1073742701"></A><TT clasS="monofont">map()</TT> function). The result is concatenated and reduced into a single variable <Tt claSS="monofont">sys.argv.</TT> The concatenation operation is performed by the <a namE="idx1073742702"></A><A Name="idx1073742703"></a><tt class="monofont">operator.add()</tt> function.<a name="idx1073742704"></a><a NamE="idx1073742705"></a><a nAme="idx1073742706"></a><a Name="idx1073742707"></A></P>
</FOnt>
<P><TABLE width="100%" border=0><TR valign="top"><TD><font size=1 color="#C0C0C0"><br></font></TD><TD align=right><font size=1 color="#C0C0C0">Last updated on 1/30/2002<br>Python Developer's Handbook, © 2002 Sams Publishing</font></TD></TR></TABLE></P>
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<br><TABLE width=100% bgcolor=white border=0 cellspacing=0 cellpadding=5><TR><TD><H4 class=Title>Index terms contained in this section</H4>
<font size=2>
functions<BR>
<a href="#idx1073742699">glob.glob()</a><BR>
<a href="#idx1073742701">map()</a><BR>
<a href="#idx1073742703">operator.add()</a><BR>
<a href="#idx1073742698">glob.glob() function</a><BR>
libraries<BR>
<a href="#idx1073742704">Python Services</a><BR>
<a href="#idx1073742700">map() function</a><BR>
modules<BR>
<a href="#idx1073742707">operator</a><BR>
<a href="#idx1073742706">operator module</a><BR>
<a href="#idx1073742702">operator.add() function</a><BR>
<a href="#idx1073742705">Python Services</a><BR>
<BR>
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